Wednesday 17 July 2024

Can you safely take Bumetanide or Acetazolamide (Diamox) if you have a Sulfonamide allergy?

I was contacted by a reader in Italy whose child with autism may respond to bumetanide, but has a sulfonamide allergy and got a skin reaction (hives). She had to stop giving the drug, but wanted to know how she could re-start bumetanide.

Other readers have pointed out how they dare not try bumetanide because they know their child has a sulfonamide allergy. I think our longtime reader Tanya is one example.


Key Point to Note

Most people discover their sulfonamide after being giving an antibiotic in early childhood.

It is now well established that many (but not all) people with an allergy to sulfonamide antibiotics can safely take a sulfonamide diuretic like Bumetanide or Diamox/Acetazolamide. This is presented in case studies later in this post.


Sulfonamide Drugs

Many common drugs are “sulfonamides”. Their chemical structure includes a sulfonyl (–SO2) group attached to an amine group (–NH2). They include common antibiotics, like erythromycin, many diuretics (bumetanide, furosemide, acetazolamide (Diamox), some anticonvulsants (zonisamide) and some anti-inflammatory drugs (sulfasalazine).


Sulfonamide Allergy

Many parents discover early in their child’s life that their child has a sulfonamide allergy. Sometimes this is abbreviated to a “sulfa allergy.”

The symptoms of a sulfonamide allergy can vary but may include:

  • Skin reactions (rash, hives, or itching)
  • Fever
  • Swelling
  • Respiratory issues (shortness of breath)
  • Anaphylaxis (in severe cases)

Usually the symptoms are minor, but once diagnosed the parents usually take note never to give their child any sulfonamide drug.


If you have the allergy must you avoid all sulfonamide drugs?

The standard assumption has been that if you have a sulfonamide allergy you cannot take Bumetanide or Acetazolamide (Diamox).

Upon further investigation in the research, this may not always be true.


What happens when there is no alternative drug?

When treating ion channel/transporter dysfunctions there may not be a non-sulfonamide alternative.

Acetazolamide (Diamox) is documented in the literature as a case in point. Bumetanide has not yet made it to the literature.

Furosemide fortunately has been researched and a safe desensitization protocol exists. Furosemide is a very similar drug to bumetanide.


Desensitization strategies

I did recently write about enzyme potentiated desensitization, which is an old, mostly overlooked, technique to overcome allergic reactions. I was interested in pollen allergy.

The best-known kinds of desensitization are allergy shots and more recently overcoming nut allergies, which gets media attention. 

Oral immunotherapy for peanut allergy in young children

The study also found that the youngest children and those who started the trial with lower levels of peanut-specific antibodies were most likely to achieve remission. 

“The landmark results of the trial suggest a window of opportunity in early childhood to induce remission of peanut allergy through oral immunotherapy,” says NIAID Director Dr. Anthony Fauci. “It is our hope that these study findings will inform the development of treatment modalities that reduce the burden of peanut allergy in children.”


I did wonder that if it works for nuts then why not bumetanide.

It turns out that I am not the first to consider desensitization to a drug allergy. The best known method is rapid drug desensitization (RDD), usually intravenous, which opens a window to be able to start taking a drug you are allergic to. Once you stop taking the drug, you then again become allergic to it.

The other approach is more like dealing with nut allergies, it is called slow drug desensitization (SDD) and involves taking a tiny initial dose and then slowly increasing it over weeks and months.

Drug desensitization is normally done in hospital as part of some therapy when you absolutely must have a drug that you are allergic to.

The paper below contains information on a very large number of common drugs where drug desensitization has been successfully carried out.


Desensitization for the prevention of drug hypersensitivity reactions

Drug desensitization is the temporary induction of tolerance to a sensitized drug by administering slow increments of the drug, starting from a very small amount to a full therapeutic dose. It can be used as a therapeutic strategy for patients with drug hypersensitivity when no comparable alternatives are available. Desensitization has been recommended for immunoglobulin E (IgE)-mediated immediate hypersensitivity; however, its indications have recently been expanded to include non-IgE-mediated, non-immunological, or delayed T cell-mediated reactions. Currently, the mechanism of desensitization is not fully understood. However, the attenuation of various intracellular signals in target cells is an area of active research, such as high-affinity IgE receptor (FcɛRI) internalization, anti-drug IgG4 blocking antibody, altered signaling pathways in mast cells and basophils, and reduced Ca2+ influx. Agents commonly requiring desensitization include antineoplastic agents, antibiotics, antituberculous agents, and aspirin/nonsteroidal anti-inflammatory drugs. Various desensitization protocols (rapid or slow, multi-bag or one-bag, with different target doses) have been proposed for each drug. An appropriate protocol should be selected with the appropriate concentration, dosage, dosing interval, and route of administration. In addition, the protocol should be adjusted with consideration of the severity of the initial reaction, the characteristics of the drug itself, as well as the frequency, pattern, and degree of breakthrough reactions.

Two categories of desensitization protocols are currently available: RDD and slow drug desensitization (SDD). RDD is recommended for immediate reactions, both allergic and nonallergic. The most widely used RDD protocol is doubling the dosage every 15 minutes until the therapeutic dose is achieved. SDD is recommended for type IV delayed hypersensitivity reactions with T cell involvement, and can be performed both orally and intravenously. There is as yet no consensus on SDD protocols, including the initial dose, dose increments between steps, and dosing interval. Further clinical experience and research are required to establish the role and efficacy of desensitization for delayed reactions.

H1 blockers, H2 blockers, and glucocorticoids can be used as premedication. Aspirin and montelukast block the end products of the arachidonic acid cascade and decrease the incidence and severity of BTRs. NSAIDs can help to control the symptoms of cytokine release syndrome. Glucocorticoids alone are not recommended because they cannot prevent the initial degranulation of mast cells. 

The desensitization process is known to be antigen-specific, as the level of drug-specific immunoglobulin E (IgE) decreases but the levels of other allergen-specific IgE remain consistent throughout the treatment period. However, the cellular and molecular mechanisms underlying drug desensitization are not yet fully understood.

Aspirin/NSAID desensitization is considered for patients with cardiovascular or musculoskeletal diseases who require aspirin or NSAID administration for prolonged periods.

The temporary tolerance to aspirin/NSAIDs lasts 48 to 72 hours after desensitization. Therefore, hypersensitivity reactions can recur 2 to 5 days after discontinuation if the therapeutic dose is not continued.


DHR to β-lactams, such as penicillin or cephalosporin, is more common than that to non-β-lactams. Desensitization can be performed for both immediate and delayed hypersensitivity reactions. The protocol should be selected based on patient characteristics, hospital capacity, and physician preferences. It is generally started with 1/1,000 of the therapeutic dose and then increased by 2 to 3-fold every 15 minutes to 5 hours. Oral administration is preferred due to its ease, safety, and effectiveness. Desensitization to penicillin and cephalosporins has been well established. Successful desensitization has also been reported for other β-lactams, such as carbapenem and monobactam, and non-β-lactams, such as vancomycin, clindamycin, metronidazole, macrolides, aminoglycosides, tetracycline, and ciprofloxacin.

Successful desensitization to other antimicrobials has also been reported for antifungals, such as amphotericin B, fluconazole, itraconazole, voriconazole, and micafungin, and for antivirals, such as acyclovir, valganciclovir, ribavirin, and nevirapine.


Furosemide desensitization

There is no literature specific to bumetanide but there is on the very similar drug furosemide.



Furosemide is a commonly used loop diuretic that contains a sulfonamide group. Although there are rare reports of hypersensitivity to furosemide, severe reactions, including anaphylaxis, have been reported. Ethacrynic acid, the only loop diuretic without a sulfonamide moiety, is no longer available in oral formulation, thus posing a dilemma in the outpatient treatment of patients with furosemide allergy.

Published protocols for furosemide desensitization include rapid intravenous administration and oral protocols lasting 3 to 10 days.3–5 The oral protocols were performed in patients with non–type I hypersensitivity reactions. We present a rapid, oral protocol for desensitization in a patient with presumed type 1 furosemide allergy manifesting as urticaria.


Desensitization to sulfonamide-containing antibiotics has been extensively used, but desensitization to furosemide is uncommon. The oral protocols previously described took 3 to 10 days and were performed in patients with non–type I hypersensitivity reactions, one with pancytopenia and the other with pancreatitis. The patient with a type I hypersensitivity reaction underwent an intravenous desensitization protocol. Rapid oral desensitization to a loop diuretic has not been previously described. The potential advantages of oral desensitization are that it is probably safer than intravenous desensitization, it may be more cost-effective in terms of monitoring and staff requirements, and it may be possible to perform in an outpatient setting. We propose our protocol as a novel approach to furosemide desensitization therapy for patients with non–life threatening reactions to furosemide. Further progress in the diagnosis and treatment of hypersensitivity to sulfonamide drugs will require identification of the major antigenic determinant and standardization of skin testing and specific IgE testing.

I think we should say good work to Dr Naureen Alim, then at Baylor College of Medicine Houston, Texas.

If anyone wants to desensitize to a bumetanide allergy I think she is the one to contact for advice. She is easy to find via Google. 

Here is another case example. 

Desensitization therapy in a patient with furosemide allergy

Allergy to furosemide is a rare phenomenon. Desensitization to this sulfa-containing drug has not been frequently performed. We describe a patient with severe congestive heart failure and type I allergy to furosemide. Because of the severity of her condition, we decided to use a rapid intravenous desensitization protocol. Following the desensitization, the patient was treated with intravenous and oral furosemide with a dramatic improvement in her clinical state. We suggest that rapid desensitization may be a safe and effective way of introducing furosemide to allergic patients for whom loop diuretics are urgently indicated.


In the case of Acetazolamide, here is one published desensitization method:


Desensitization to acetazolamide in a patient with previous antimicrobial sulfonamide allergy

Acetazolamide is a carbonic anhydrase inhibitor that is frequently used in the management of idiopathic intracranial hypertension. Acetazolamide is a sulfonamide agent; specifically, it is a non sulfonylarylamine, which lacks the amine moiety found at the N4 position that is seen in sulfa antibiotics. 

Sulfonamide antibiotics contain a substituted ring at the N1 position that is thought to be the driving factor in immediate hypersensitivity reactions.  

Although sulfa allergies are commonly reported, there is no evidence to suggest cross-reactivity between sulfonamide antibiotics and sulfonamide nonantibiotics. However, patients can report a history of allergy to both categories of drugs. We present a rapid desensitization protocol to acetazolamide in a patient with history of immediate hypersensitivity reactions to both a sulfonamide antibiotic and acetazolamide. 

We formulated a 12-step intravenous protocol that was performed in the intensive care unit setting (Table 1). Informed consent was provided by the patient, and she tolerated the procedure well without any adverse reactions. The desensitization procedure took 395 minutes or approximately 6.5 hours. She was monitored overnight in the hospital and was observed the following morning after taking 500 mg of acetazolamide orally to ensure tolerance. She was thereafter able to continue her recommended dose of acetazolamide without any issues to date.


Allergy to a sulfonamide antibiotic does not always mean you will be allergic to the non-antibiotic sulfonamide drugs.


Use of Acetazolamide in Sulfonamide-Allergic Patients With Neurologic Channelopathies

The 3 patients had been considered for carbonic anhydrase inhibitor treatment but a pharmacist had refused to fill a prescription for acetazolamide for 1 patient and the other 2 patients were denied treatment because of the allergy history. All 3 patients were prescribed acetazolamide and had no adverse reaction. Two patients improved substantially and are continuing treatment. A review of the pharmacology literature suggests that cross-reactivity between antibiotic and nonantibiotic carbonic anhydrase inhibitors is unlikely. Moreover, a review of case reports does not suggest cross-reactivity. Previous reports in the ophthalmology literature also indicate that acetazolamide can be administered to patients with a history of antibiotic sulfonamide allergic reaction.


These 3 cases confirm that the carbonic anhydrase inhibitor acetazolamide can be given to patients with a history of allergic skin rash with antibiotic sulfonamide.


Acetazolamide has been used for the treatment of episodic ataxia type 2, with benefit in 50% to 75% of patients. In episodic ataxia type 1, acetazolamide was also effective in decreasing attack frequency. Acetazolamide is also effective in the periodic paralyses. Carbonic anhydrase inhibitors have been used to prevent altitude sickness, to lower intraocular pressure in open-angle glaucoma, and to treat refractory absence, myoclonic, and catamenial epilepsy as part of multidrug regimens. Acetazolamide has recently been used for hemiplegic migraine and idiopathic intracranial hypertension. 

The lack of available clinical or pharmacological evidence to support cross-reactivity between sulfonamide antibiotics and acetazolamide lends supports to the use of acetazolamide to treat patients with episodic ataxia and periodic paralysis. Of our 3 sulfonamide-allergic patients, 2 improved in symptoms after treatment with acetazolamide and none of the 3 had a hypersensitivity reaction. We conclude that a sulfonamide allergy should not be a contraindication to treatment with acetazolamide in patients with neurologic channelopathies. 


Acetazolamide and sulfonamide allergy: a not so simple story

 Allergies and adverse reactions to sulfonamide medications are quite common. Two distinct categories of drugs are classified as sulfonamides: antibiotics and nonantibiotics. The two groups differ in their chemical structure, use, and the rate at which adverse reactions occur. Cross-reactivity between the two groups has been implied in the past, but is suspect. Acetazolamide, from the nonantibiotic group, is routinely used in the prevention and treatment of high altitude issues and may not need to be avoided in individuals with a history of sulfonamide allergy. This review addresses the differences between the groups and the propensity for intergroup and intragroup adverse reactions based on the available literature. We also examine the different clinical presentations of allergy and adverse reactions, from simple cutaneous reactions with no sequelae through Stevens-Johnson syndrome and anaphylaxis, with risk for significant morbidity and mortality. We offer a systematic approach to determine whether acetazolamide is a safe option for those with a history of allergy to sulfonamides.

Sulfonamide-containing antibiotics are the second most frequent cause of allergic drug reactions, after the b-lactams (penicillins and cephalosporins). In one large study, the incidence of reactions to trimethoprim–sulfamethoxazole (TMPSMX) was 3% of patients exposed, compared with 5% for amoxicillin. The incidence of reactions to nonantibiotic sulfonamides is not well established; it is clearly less than with antibiotics.


There are several approaches to the use of sulfonamide drugs (specifically acetazolamide) in patients with past reactions to this class of medications. The choice of strategy depends on the type and severity of the previous reaction, as well as the class of drug (antibiotic versus non antibiotic) and the risk–benefit profile for the patient. However, regardless of the approach, the risks of subsequent reactions cannot be completely eliminated, and a thorough discussion between the medical provider and the patient should include this point so that an informed decision regarding the use of acetazolamide can be made. The safest approach for the patient with any prior reaction to a sulfa drug, multiple drug allergies, or penicillin allergy would be to avoid all drugs in the sulfonamide group, including acetazolamide.


Avoidance of the entire sulfonamide drug group is warranted for individuals whose previous reaction included a serious and/or life-threatening condition such as anaphylaxis, SJS, and TEN. Any form of reexposure to the precipitating drug or a sulfonamide in the same group is strictly contraindicated. Published evidence has shown that SJS/TEN can recur with even minor reexposures and may be more severe in the second episode. Even though SJS/TEN reactions are so far not associated with nonantibiotic sulfonamides, because of the severity and life-threatening nature of these reactions, a safe practice is to avoid all sulfonamides in patients with past SJS or TEN from sulfonamide containing medications.


This paper was published in a journal on high altitude medicine. That is why the suggested alternatives are staged ascents of the mountain and oxygen.



The first key point is that you can have an allergy to sulfonamide antibiotics and have absolutely no negative reaction to sulfonamide drugs like bumetanide and acetazolamide (Diamox).

If you do have a mild allergic reaction to a sulfonamide drug, there are desensitization strategies that are proven to work in many people.

It looks like rapid oral desensitization to bumetanide and acetazolamide is likely possible, based on what has been shown possible with furosemide and a wide variety of other drugs.

Clearly the level of sensitivity and hence the nature of the allergic reaction can vary massively from person to person, this is why rapid desensitization usually takes place in hospital.

If you opt for the slower process, much less is known, because it is not generally used. If you did it in hospital it would require a very long stay and so would be hugely expensive.

It is suggested that slow drug desensitization (SDD) should be much more long lasting and hopefully might become permanent – as is the hope for nut allergy treatment.

When posed the initial question by our reader wanting to use bumetanide, I was thinking along the lines of slow drug desensitization (SDD), because this is how you would treat a pollen allergy. If rapid oral desensitization will work for taking bumetanide once a day that would be great. To maintain the protection from allergy it might be safer to take a small second daily dose.


Here is a quick overview of desensitization options for sulfonamide allergy:

  • Rapid Desensitization (RDD):
    • Faster process (hours)
    • Temporary tolerance achieved
    • May be repeated if needed
  • Slow Desensitization (SDD):
    • Slower process (days, weeks, or months)
    • Might offer a greater chance of longer-lasting
    • Still requires close monitoring

Important Considerations:

  • Always consult your doctor: They can assess your allergy severity, treatment options, and the suitability of desensitization if necessary.
  • Desensitization is not without risks: It requires careful monitoring.


I for one found this an interesting investigation and with promise for parents of those with severe autism who have been unable to trial Bumetanide due to a sulfonamide allergy. 

Hopefully our reader Dr Antonucci will follow up on this and make a bumetanide desensitization protocol for those people with autism and a sulfonamide allergy. Maybe he has already done it. It looks very achievable.

Sunday 16 June 2024

Taurine for subgroups of Autism? Plus, vitamin B5 and L Carnitine for KAT6A syndrome?


   A Red Bull Formula 1 racing car


Today’s post should be of wide interest because it concerns the potential benefit from the OTC supplement taurine. There is a section at the end answering a query about mutations in the KAT6A gene.

Taurine is an amino acid and it is found in abundance in both mother’s milk and formula milk.  It has long been used as a supplement by some people with autism. It is finally going to be the subject of a clinical trial in autism and not surprisingly that will be in China - nowadays home to much autism research.

Taurine is also a key ingredient in energy drinks like Red Bull.


In a study of children with autism a third had low levels of taurine. Since taurine has anti-oxidant activity, children with ASD with low taurine concentrations were then examined for abnormal mitochondrial function. That study suggests that taurine may be a valid biomarker in a subgroup of ASD.

Taurine has several potential benefits to those with autism and it is already used to treat a wide variety of other conditions, some of which are relevant to autism. One example is its use in Japan to improve mitochondrial function in a conditional called MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes).

The effects that are suggested to relate to some types of autism include:-


·        Activating GABAA receptors, in the short term

·        Down regulating GABAA receptors, after long term use

·        Enhancing the PTEN/mTOR/AKT pathway

·        Reverse autophagy impairment caused by microglial activation

·        Reduce NMDA mediated activation of calcium channels

·        Protective effect on mitochondria and upregulating Complex 1

·        Improving the quality of the gut microbiota


If you have a pet you may know that taurine is widely given to cats and dogs. All cat food has taurine added and some breeds of dog need supplementation.

Taurine is crucial for several bodily functions in pets, including: 

Heart Health: Taurine helps regulate heart rhythm and improves heart muscle function. It can help prevent a type of heart disease called dilated cardiomyopathy (DCM) in both cats and dogs.

Vision: Taurine plays a role in maintaining healthy vision and can prevent retinal degeneration, a serious eye disease.

Immune System Function: Taurine may help boost the immune system and fight off infections.


From China we have the following recent study showing a benefit in the BTBR model of autism:

Taurine Improved Autism-Like Behaviours and Defective Neurogenesis of the Hippocampus in BTBR Mice through the PTEN/mTOR/AKT Signalling Pathway

Effective treatment of patients with autism spectrum disorder (ASD) is still absent so far. Taurine exhibits therapeutic effects towards the autism-like behaviour in ASD model animals. Here, we determined the mechanism of taurine effect on hippocampal neurogenesis in genetically inbred BTBR T+ tf/J (BTBR) mice, a proposed model of ASD. In this ASD mouse model, we explored the effect of oral taurine supplementation on ASD-like behaviours in an open field test, elevated plus maze, marble burying test, self-grooming test, and three-chamber test. The mice were divided into four groups of normal controls (WT) and models (BTBR), who did or did not receive 6-week taurine supplementation in water (WT, WT+ Taurine, BTBR, and BTBR+Taurine). Neurogenesis-related effects were determined by Ki67 immunofluorescence staining. Western blot analysis was performed to detect the expression of phosphatase and tensin homologue deleted from chromosome 10 (PTEN)/mTOR/AKT pathway-associated proteins. Our results showed that taurine improved the autism-like behaviour, increased the proliferation of hippocampal cells, promoted PTEN expression, and reduced phosphorylation of mTOR and AKT in hippocampal tissue of the BTBR mice. In conclusion, taurine reduced the autism-like behaviour in partially inherited autism model mice, which may be associa­ted with improving the defective neural precursor cell proliferation and enhancing the PTEN-associated pathway in hippocampal tissue.


A trial in humans with autism is scheduled in Guizhou, China. In this trial they seem to believe the benefit may come from modification to the gut microbiota.


Study on the Treatment of Taurine in Children With Autism

In the treatment of autism spectrum disorders (ASD), medication is only an adjunct, and the main treatment modalities are education and behavioral therapy. People with autism incur huge medical and educational costs, which puts a great financial burden on families. Taurine is one of the abundant amino acids in tissues and organs, and plays a variety of physiological and pharmacological functions in nervous, cardiovascular, renal, endocrine and immune systems. A large number of studies have shown that taurine can improve cognitive function impairment under various physiological or pathological conditions through a variety of mechanisms, taurine can increase the abundance of beneficial bacteria in the intestine, inhibit the growth of harmful bacteria, and have a positive effect on intestinal homeostasis. This study intends to analyze the effect of taurine supplementation on ASD, and explore the possible mechanism by detecting intestinal symptoms, intestinal flora, markers of oxidative stress and clinical symptoms of ASD.

Taurine granules mixed with corn starch and white sugar, 0.4g in 1 bag, taken orally. One time dosage: 1 bag each time for 1-2 years old, 3 times a day, 1.5 bags each time for 3-5 years old, 3 times a day, 2 bags each time for 6-8 years old, 3 times a day, 2.5-3 bags each time for 9-13 years old, 3 to 4 bags each time for children and adults over 14 years old, 3 times a day. The use of taurine is strictly in accordance with the specifications of Chinese Pharmacopoeia. 


Roles of taurine in cognitive function of physiology, pathologies and toxication

Taurine is a key functional amino acid with many functions in the nervous system. The effects of taurine on cognitive function have aroused increasing attention. First, the fluctuations of taurine and its transporters are associated with cognitive impairments in physiology and pathology. This may help diagnose and treat cognitive impairment though mechanisms are not fully uncovered in existing studies. Then, taurine supplements in cognitive impairment of different physiologies, pathologies and toxicologies have been demonstrated to significantly improve and restore cognition in most cases. However, elevated taurine level in cerebrospinal fluid (CSF) by exogenous administration causes cognition retardations only in physiologically sensitive period between the perinatal to early postnatal period. In this review, taurine levels are summarized in different types of cognitive impairments. Subsequently, the effects of taurine supplements on cognitions in physiology, different pathologies and toxication of cognitive impairments (e.g. aging, Alzheimer' disease, streptozotocin (STZ)-induced brain damage, ischemia model, mental disorder, genetic diseases and cognitive injuries of pharmaceuticals and toxins) are analyzed. These data suggest that taurine can improve cognition function through multiple potential mechanisms (e.g. restoring functions of taurine transporters and γ-aminobutyric acid (GABA) A receptors subunit; mitigating neuroinflammation; up-regulating Nrf2 expression and antioxidant capacities; activating Akt/CREB/PGC1α pathway, and further enhancing mitochondria biogenesis, synaptic function and reducing oxidative stress; increasing neurogenesis and synaptic function by pERK; activating PKA pathway). However, more mechanisms still need explorations.


Effects and Mechanisms of Taurine as a Therapeutic Agent

Taurine as an inhibitory neuromodulator

Although ER stress assumes an important role in the cytoprotective actions of taurine in the central nervous system (CNS), another important mechanism affecting the CNS is the neuromodulatory activity of taurine. Toxicity in the CNS commonly occurs when an imbalance develops between excitatory and inhibitory neurotransmitters. GABA is one of the dominant inhibitory neurotransmitters, therefore, reductions in either the CNS levels of GABA or the activity of the GABA receptors can favor neuronal hyperexcitability. Taurine serves as a weak agonist of the GABAA, glycine and NMDA receptors Therefore, taurine can partially substitute for GABA by causing inhibition of neuronal excitability. However, the regulation of the GABAA receptor by taurine is complex. While acute taurine administration activates the GABAA receptor, chronic taurine feeding promotes the downregulation of the GABAA receptor  and the upregulation of glutamate decarboxylase, the rate-limiting step in GABA biosynthesis. Therefore, complex interactions within the GABAeric system, as well as in the glycine and NMDA receptors, largely define the actions of taurine in the CNS.

Pharmacological characterization of GABAA receptors in taurine-fed mice


Taurine is one of the most abundant free amino acids especially in excitable tissues, with wide physiological actions. Chronic supplementation of taurine in drinking water to mice increases brain excitability mainly through alterations in the inhibitory GABAergic system. These changes include elevated expression level of glutamic acid decarboxylase (GAD) and increased levels of GABA. Additionally we reported that GABAA receptors were down regulated with chronic administration of taurine. Here, we investigated pharmacologically the functional significance of decreased / or change in subunit composition of the GABAA receptors by determining the threshold for picrotoxin-induced seizures. Picrotoxin, an antagonist of GABAA receptors that blocks the channels while in the open state, binds within the pore of the channel between the β2 and β3 subunits. These are the same subunits to which GABA and presumably taurine binds.


Two-month-old male FVB/NJ mice were subcutaneously injected with picrotoxin (5 mg kg-1) and observed for a) latency until seizures began, b) duration of seizures, and c) frequency of seizures. For taurine treatment, mice were either fed taurine in drinking water (0.05%) or injected (43 mg/kg) 15 min prior to picrotoxin injection. 


We found that taurine-fed mice are resistant to picrotoxin-induced seizures when compared to age-matched controls, as measured by increased latency to seizure, decreased occurrence of seizures and reduced mortality rate. In the picrotoxin-treated animals, latency and duration were significantly shorter than in taurine-treated animas. Injection of taurine 15 min before picrotoxin significantly delayed seizure onset, as did chronic administration of taurine in the diet. Further, taurine treatment significantly increased survival rates compared to the picrotoxin-treated mice. 


We suggest that the elevated threshold for picrotoxin-induced seizures in taurine-fed mice is due to the reduced binding sites available for picrotoxin binding due to the reduced expression of the beta subunits of the GABAA receptor. The delayed effects of picrotoxin after acute taurine injection may indicate that the two molecules are competing for the same binding site on the GABAA receptor. Thus, taurine-fed mice have a functional alteration in the GABAergic system. These include: increased GAD expression, increased GABA levels, and changes in subunit composition of the GABAA receptors. Such a finding is relevant in conditions where agonists of GABAA receptors, such as anesthetics, are administered.


Taurine as used in Japan to treat MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes)

Taurine powder 98% "Taisho" [Prevention of stroke-like episodes of MELAS]

Effects of this medicine

This medicine improves mitochondrial dysfunction related to cell energy production etc., and suppresses stroke-like episodes.
It is usually used for prevention of stroke-like episodes of MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes).

·         Your dosing schedule prescribed by your doctor is ((        to be written by a healthcare professional))

·         In general, take as following dose according to your weight, 3 times a day after meals. If you weigh less than 15 kg, take 1.02 g (1 g of the active ingredient) at a time. If your weight ranges 15 kg to less than 25 kg, take 2.04 g (2 g) at a time. If your weight ranges 25 kg to less than 40 kg, take 3.06 g (3 g) at a time. If you weigh 40 kg and more, take 4.08 g (4 g) at a time. Strictly follow the instructions.

·         If you miss a dose, take the missed a dose as soon as possible. However, if it is almost time for the next dose, skip the missed a dose and continue your regular dosing schedule. You should never take two doses at one time.

·         If you accidentally take more than your prescribed dose, consult with your doctor or pharmacist.

·         Do not stop taking this medicine unless your doctor instructs you to do so.


On the Potential Therapeutic Roles of Taurine in Autism Spectrum Disorder


Contemporary research has found that people with autism spectrum disorder (ASD) exhibit aberrant immunological function, with a shift toward increased cytokine production and unusual cell function. Microglia and astroglia were found to be significantly activated in immuno-cytochemical studies, and cytokine analysis revealed that the macrophage chemoattractant protein-1 (MCP-1), interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), and transforming growth factor β-1 (TGFB-1), all generated in the neuroglia, constituted the most predominant cytokines in the brain. Taurine (2-aminoethanesulfonic acid) is a promising therapeutic molecule able to increase the activity of antioxidant enzymes and ATPase, which may be protective against aluminum-induced neurotoxicity. It can also stimulate neurogenesis, synaptogenesis, and reprogramming of proinflammatory M1 macrophage polarization by decreasing mitophagy (mitochondrial autophagy) and raising the expression of the markers of the anti-inflammatory and pro-healing M2 macrophages, such as macrophage mannose receptor (MMR, CD206) and interleukin 10 (IL-10), while lowering the expression of the M1 inflammatory factor genes. Taurine also induces autophagy, which is a mechanism that is impaired in microglia cells and is critically associated with the pathophysiology of ASD. We hypothesize here that taurine could reprogram the metabolism of M1 macrophages that are overstimulated in the nervous system of people suffering from ASD, thereby decreasing the neuroinflammatory process characterized by autophagy impairment (due to excessive microglia activation), neuronal death, and improving cognitive functions. Therefore, we suggest that taurine can serve as an important lead for the development of novel drugs for ASD treatment.


Taurine as a potential therapeutic agent interacting with multiple signaling pathways implicated in autism spectrum disorder (ASD): An in-silico analysis


Autism spectrum disorders (ASD) are a complex sequelae of neurodevelopmental disorders which manifest in the form of communication and social deficits. Currently, only two agents, namely risperidone and aripiprazole have been approved for the treatment of ASD, and there is a dearth of more drugs for the disorder. The exact pathophysiology of autism is not understood clearly, but research has implicated multiple pathways at different points in the neuronal circuitry, suggesting their role in ASD. Among these, the role played by neuroinflammatory cascades like the NF-KB and Nrf2 pathways, and the excitotoxic glutamatergic system, are said to have a bearing on the development of ASD. Similarly, the GPR40 receptor, present in both the gut and the blood brain barrier, has also been said to be involved in the disorder. Consequently, molecules which can act by interacting with one or multiple of these targets might have a potential in the therapy of the disorder, and for this reason, this study was designed to assess the binding affinity of taurine, a naturally-occurring amino acid, with these target molecules. The same was scored against these targets using in-silico docking studies, with Risperidone and Aripiprazole being used as standard comparators. Encouraging docking scores were obtained for taurine across all the selected targets, indicating promising target interaction. But the affinity for targets actually varied in the order NRF-KEAP > NF-κB > NMDA > Calcium channel > GPR 40. Given the potential implication of these targets in the pathogenesis of ASD, the drug might show promising results in the therapy of the disorder if subjected to further evaluations.


Is Taurine a Biomarker in Autistic Spectrum Disorder?

Taurine is a sulfur-containing amino acid which is not incorporated into protein. However, taurine has various critical physiological functions including development of the eye and brain, reproduction, osmoregulation, and immune functions including anti-inflammatory as well as anti-oxidant activity. The causes of autistic spectrum disorder (ASD) are not clear but a high heritability implicates an important role for genetic factors. Reports also implicate oxidative stress and inflammation in the etiology of ASD. Thus, taurine, a well-known antioxidant and regulator of inflammation, was investigated here using the sera from both girls and boys with ASD as well as their siblings and parents. Previous reports regarding taurine serum concentrations in ASD from various laboratories have been controversial. To address the potential role of taurine in ASD, we collected sera from 66 children with ASD (males: 45; females: 21, age 1.5-11.5 years, average age 5.2 ± 1.6) as well as their unaffected siblings (brothers: 24; sisters: 32, age 1.5-17 years, average age 7.0 ± 2.0) as controls of the children with ASD along with parents (fathers: 49; mothers: 54, age 28-45 years). The sera from normal adult controls (males: 47; females: 51, age 28-48 years) were used as controls for the parents. Taurine concentrations in all sera samples were measured using high performance liquid chromatography (HPLC) using a phenylisothiocyanate labeling technique. Taurine concentrations from female and male children with ASD were 123.8 ± 15.2 and 145.8 ± 8.1 μM, respectively, and those from their unaffected brothers and sisters were 142.6 ± 10.4 and 150.8 ± 8.4 μM, respectively. There was no significant difference in taurine concentration between autistic children and their unaffected siblings. Taurine concentrations in children with ASD were also not significantly different from their parents (mothers: 139.6 ± 7.7 μM, fathers: 147.4 ± 7.5 μM). No significant difference was observed between adult controls and parents of ASD children (control females: 164.8 ± 4.8 μM, control males: 163.0 ± 7.0 μM). However, 21 out of 66 children with ASD had low taurine concentrations (<106 μM). Since taurine has anti-oxidant activity, children with ASD with low taurine concentrations will be examined for abnormal mitochondrial function. Our data imply that taurine may be a valid biomarker in a subgroup of ASD.


The Role of Taurine in Mitochondria Health: More Than Just an Antioxidant

Taurine is a naturally occurring sulfur-containing amino acid that is found abundantly in excitatory tissues, such as the heart, brain, retina and skeletal muscles. Taurine was first isolated in the 1800s, but not much was known about this molecule until the 1990s. In 1985, taurine was first approved as the treatment among heart failure patients in Japan. Accumulating studies have shown that taurine supplementation also protects against pathologies associated with mitochondrial defects, such as aging, mitochondrial diseases, metabolic syndrome, cancer, cardiovascular diseases and neurological disorders. In this review, we will provide a general overview on the mitochondria biology and the consequence of mitochondrial defects in pathologies. Then, we will discuss the antioxidant action of taurine, particularly in relation to the maintenance of mitochondria function. We will also describe several reported studies on the current use of taurine supplementation in several mitochondria-associated pathologies in humans.


Taurine is known not as a radical scavenger. Several potential mechanisms by which taurine exerts its antioxidant activity in maintaining mitochondria health include: taurine conjugates with uridine on mitochondrial tRNA to form a 5-taurinomethyluridine for proper synthesis of mitochondrial proteins (mechanism 1), which regulates the stability and functionality of respiratory chain complexes; taurine reduces superoxide generation by enhancing the activity of intracellular antioxidants (mechanism 2); taurine prevents calcium overload and prevents reduction in energy production and the collapse of mitochondrial membrane potential (mechanism 3); taurine directly scavenges HOCl to form N-chlorotaurine in inhibiting a pro-inflammatory response (mechanism 4); and taurine inhibits mitochondria-mediated apoptosis by preventing caspase activation or by restoring the Bax/Bcl-2 ratio and preventing Bax translocation to the mitochondria to promote apoptosis (mechanism 5).

Taurine Forms a Complex with Mitochondrial tRNA

Taurine Reduces Superoxide Generation in the Mitochondria

Taurine Regulates Intracellular Calcium Homeostasis

Taurine Inhibits Mitochondria-Mediated Apoptosis


Taurine therapy, therefore, could potentially improve mitochondrial health, particularly in mitochondria-targeted pathologies, such as cardiovascular diseases, metabolic diseases, mitochondrial diseases and neurological disorders. Whether the protective mechanism on mitochondria primarily relies on the taurine modification of mitochondrial tRNA requires further investigation.


Taurine and the gut microbiota 

We now regularly in the research see that you can make changes in the gut microbiota to treat medical conditions. I think the most interesting was the discovery that the ketogenic diet, used for a century to treat epilepsy, actually works via the high fat diet changing the bacteria that live in your gut; it has nothing at all to do with ketones. UCLA are developing a bacteria product that will mimic the effect of this diet.

We should not be surprised to see that one mode of action put forward for Taurine is changes it makes in the gut microbiota.  It is this very mechanism that the Chinese researchers think is relevant to its benefit in autism.

The paper below is not about autism, but it is about Taurine’s effect on the gut microbiota.

Effects of Taurine on Gut Microbiota Homeostasis: An Evaluation Based on Two Models of Gut Dysbiosis

Taurine, an abundant free amino acid, plays multiple roles in the body, including bile acid conjugation, osmoregulation, oxidative stress, and inflammation prevention. Although the relationship between taurine and the gut has been briefly described, the effects of taurine on the reconstitution of intestinal flora homeostasis under conditions of gut dysbiosis and underlying mechanisms remain unclear. This study examined the effects of taurine on the intestinal flora and homeostasis of healthy mice and mice with dysbiosis caused by antibiotic treatment and pathogenic bacterial infections. The results showed that taurine supplementation could significantly regulate intestinal microflora, alter fecal bile acid composition, reverse the decrease in Lactobacillus abundance, boost intestinal immunity in response to antibiotic exposure, resist colonization by Citrobacter rodentium, and enhance the diversity of flora during infection. Our results indicate that taurine has the potential to shape the gut microbiota of mice and positively affect the restoration of intestinal homeostasis. Thus, taurine can be utilized as a targeted regulator to re-establish a normal microenvironment and to treat or prevent gut dysbiosis.



Your body can synthesize taurine from other amino acids, particularly cysteine, with the help of vitamin B6. In most cases, this internal production is enough to meet your daily needs for basic bodily functions.

Infants and some adults may need taurine added to their diet.

Based on the small study in humans, about a third of children with autism have low levels of taurine in their blood.

Is extra taurine going to provide a benefit to the other two thirds?

Taurine looks easy to trial. It is normally taken three times a day after a meal. Each dose would be 0.4g to 4g depending on weight and what the purpose was. The 2 year olds in the Chinese autism trial will be taking 0.4g three times a day. Japanese adults with mitochondrial disease (MELAS) are taking 4g three times a day.

One can oF Red Bull contains 1g of taurine. Most supplements contain 0.5 to 1g. This is a similar dose to what is given to pet cats and dogs. Just like Red Bull contains B vitamins, so do the taurine products for cats and dogs. 

Some of the effects will be immediate, while others will take time to show effect. For example there can potentially be an increase in mitochondrial biogenesis. I expect any changes in gut bacteria would also take a long time to get established.

The effect via GABA on increasing brain excitability is an interesting one for people taking bumetanide for autism, where the GABA developmental switch did not take place. Based on the research you could argue that it will be beneficial or indeed harmful.

What I can say is that in Monty, aged 20 with ASD and taking bumetanide for 12 years, he responded very well on the rare occasions he drank Red Bull.



Vitamin B5 and L carnitine for KATA6A Syndrome

I was asked about KATA6A syndrome recently.  This syndrome is researched by Dr Kelley, the same doctor who coined the term Autism secondary to mitochondrial dysfunction (AMD).

KAT6A Research and Treatment An Update by Richard I Kelley , MD, PHD

Some kids with KATA6A, like Peter below, respond very well to Dr Kelley’s mito cocktail.


Peter’s Experience with a Mitochondrial Cocktail


Here’s my experience with the mitochondrial cocktail:

– At 4 weeks after the start of the cocktail, Peter became potty-trained during the day without any training. He pulled his pull up off, refused to put it back on.

-At 2 months, Peter started riding his bike with no training wheels and playing soccer. He became able to kick the ball and run after it till he scores.

-At 2.5 months, he started skiing independently. I used to try to teach how to ski since he was 3yo. I used to spend hours and hours picking him up off the snow with no result. I tried different kind of reinforcers (food,..) with no result. After the cocktail, he just went down the hill by himself, He can ski independently now and knows how to make turns.

-At 2-3 months, I started noticing an increased strength in playing ice hockey and street hockey with a better understanding of the game. His typing ability improved too, he used to have severe apraxia while typing (type the letter next to the letter he wants to type…).

-At 3-4 months, Peter’s fingers on the piano became stronger, he became able to play harder songs with less training and less frustration. I also noticed an increase in “common sense” like for example putting his backpack in the car instead of throwing it on the floor next to the car and riding the car without his backpack. Another example, when we go to the public library, he knows by himself that he has to go to the children section, and walks independently without showing him directions to the play area inside the children section. In the past, he used to grab books the time he enters the library, throw a tantrum on the floor. The most important milestone is that Peter started to say few words that I can understand.

-At 11 months, Peter became potty-trained at night. His speech is slowly getting clearer. His fine and gross motor skills are still getting better.


Some readers of this blog have been in touch with Dr Kelley and he does give very thorough replies.

Generally speaking, the therapies for mitochondrial diseases/dysfunctions seem to be about avoiding it getting worse, rather than making dramatic improvements. In the case of Peter (above) the effects do look dramatic. There are many other ideas in the research that do not seem to have been translated into therapy.

A study from two years ago does suggest that vitamin B5 and L carnitine should be trialed. 

Pantothenate and L-Carnitine Supplementation Improves Pathological Alterations in Cellular Models of KAT6A Syndrome

Mutations in several genes involved in the epigenetic regulation of gene expression have been considered risk alterations to different intellectual disability (ID) syndromes associated with features of autism spectrum disorder (ASD). Among them are the pathogenic variants of the lysine-acetyltransferase 6A (KAT6A) gene, which causes KAT6A syndrome. The KAT6A enzyme participates in a wide range of critical cellular functions, such as chromatin remodeling, gene expression, protein synthesis, cell metabolism, and replication. In this manuscript, we examined the pathophysiological alterations in fibroblasts derived from three patients harboring KAT6A mutations. We addressed survival in a stress medium, histone acetylation, protein expression patterns, and transcriptome analysis, as well as cell bioenergetics. In addition, we evaluated the therapeutic effectiveness of epigenetic modulators and mitochondrial boosting agents, such as pantothenate and L-carnitine, in correcting the mutant phenotype. Pantothenate and L-carnitine treatment increased histone acetylation and partially corrected protein and transcriptomic expression patterns in mutant KAT6A cells. Furthermore, the cell bioenergetics of mutant cells was significantly improved. Our results suggest that pantothenate and L-carnitine can significantly improve the mutant phenotype in cellular models of KAT6A syndrome.

Next, we analyzed the expression changes of specific genes in treated and untreated conditions. We found that the expression levels of downregulated genes in the mutant KAT6A fibroblasts, such as KAT6ASIRT1SIRT3NAMPT1Mt-ND6NDUFA9PANK2mtACPPDH (E1 subunit α2), KGDH (E2 subunit), SOD1SOD2, and GPX4 were significantly restored after pantothenate and L-carnitine treatment. The proteins encoded by these genes are involved in acetylation-deacetylation pathways, CoA metabolism, mitochondria, and antioxidant enzymes, all of which are critical for intracellular processes in embryonic and childhood development.


KAT6A acts as a master regulator by fine-tuning gene expression through chromatin modifications, so we should expect it to have wide ranging effects. All the closest interactions are will other genes that modify gene expression.

A useful site is genecards:


KAT6A mutations are indeed linked to microcephaly, a condition characterized by a smaller than average head circumference.

Most autism is associated with hyperactive pro-growth signalling pathways; only a minority is associated with the opposite and this would fit with microcephaly, which is typical in KAT6A.

Microcephaly is a very common feature of Rett syndrome.

Among the features of KAT6A syndrome there will be overlaps with other syndromes.

Dr Kelley analyses amino acids looking for mitochondrial dysfunction. He has found this present in KAT6A, but this is only one treatable feature of the syndrome.

Targeting growth signaling pathways might well be worth pursuing. You would be looking a what works in other people with smaller heads.

I wrote quite a lot about IGF-1 previously in this blog.

It would be highly plausible that these related therapies might be of benefit. The easy one to try is cGPMax, because it is sold OTC. IGF-1 itself might be beneficial, you would have to find a helpful endocrinologist to trial it.

All the therapies of idiopathic autism could be trialed.

If the child has a paradoxical reaction to any benzodiazepine drug, then you know that bumetanide is likely to be beneficial.

Since mitochondrial function is impaired in KAT6A, taurine is another thing to trial.