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.

 

RAPID ORAL DESENSITIZATION TO 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.

Conclusions

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.

  

Conclusion

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.