Sulfa Drugs List

Antibiotics and Other Sulfonamides to Avoid If You Have a Sulfa Allergy

Medically reviewed by Jurairat J. Molina, MD

Sulfa drugs are synthetic (man-made) medications made from sulfanilamide that contain antibacterial properties. Sulfa drugs were the first class of antibiotics ever discovered. However, many other medications may contain sulfa too, such as medications for diabetes, thyroiditis, and arthritis.

Some people have a sulfa allergy and need to avoid medications containing sulfonamides.

This article lists specific sulfa drugs and symptoms of an allergic reaction that could occur if you are sensitive to sulfa.

What Are Sulfanilamides?

Sulfanilamides, also called sulfonamides, are made through chemical reactions. They are an important class of antibiotics and are also used to treat a variety of health conditions, including:

• Bacterial infections, such as urinary tract infections (UTIs)

• Diuresis (removing excess fluid from the body)

• Diabetes

• Thyroiditis

• Glaucoma

• Inflammation associated with conditions, such as inflammatory bowel disease (IBD), rheumatoid arthritis, and other autoimmune conditions

• Eye infections

• Vaginitis

• Burns
  

Sulfa Drug List

Medications containing sulfonamide include:

• Bactrim and Bactrim DS (sulfamethoxazole and trimethoprim): used to treat a variety of bacterial infections

• Cotrim (Co-trimoxazole): used to treat certain bacterial infections, such as pneumonia, bronchitis, "travelers" diarrhea, and infections of the urinary tract, ears, and intestines

• Pediazole (Erythromycin/sulfisoxazole): used to treat certain ear infections in children caused by bacteria
  

• Septra and Septra DS (sulfamethoxazole and trimethoprim): used to treat a variety of bacterial infections

• Sulfadiazine: used to treat a variety of bacterial infections.

• Silvadene (silver sulfadiazine): used to prevent and treat wound infection in patients with 2nd and 3rd-degree burns.

• Sulfatrim (sulfamethoxazole and trimethoprim): used to treat a variety of bacterial infections

• Sulfacetamide: found in over-the-counter and prescription topical products

• Sulfonylureas: used to lower blood sugar in people with Type 2 diabetes

• Dorzolamide, Trusopt, Azopt, and Cosopt: used to treat glaucoma

• AVC Vaginal (sulfanilamide): used to treat vaginitis
  

Sulfonamide-containing nonantimicrobial agents include several classes of drugs. Some healthcare providers will avoid prescribing these to people with an allergy to sulfonamide-containing antimicrobials. However, research has shown that a reaction is unlikely, so they might be prescribed. These drugs include.

• Human immunodeficiency virus (HIV) antivirals such as the protease inhibitors Agenerase (amprenavir), Prezista (darunavir), Lexiva (fosamprenavir), and Aptivus (tipranavir)

• Carbonic anhydrase inhibitors such as Diamox (acetazolamide) used to treat glaucoma(increased eye pressure), epilepsy, and high-altitude sickness

• Loop diuretics (used to manage heart failure) such as Bumex (bumetanide) and Lasix (furosemide)

• Sulfonylureas (used to manage diabetes) such as Glucotrol (glipizide) and Diabeta (glyburide)

• COX-2 inhibitors (an anti-Inflammatory) such as Celebrex (celecoxib)

• Triptans (used to manage migraines) such as Imitrex (sumatriptan)

• Thiazide diuretics (used to manage heart failure and high blood pressure) such as Thalidone (chlorthalidone) and HydroDiuril (hydrochlorothiazide)

• Azulfidine (sulfasalazine) (used for inflammatory bowel disease and rheumatoid arthritis)
  

Antibiotics without Sulfa

There are many non-sulfa antibiotics that you can take in place of sulfa-containing antimicrobials. Two classes of antibiotics that don't contain sulfa are penicillins (like amoxicillin) and fluoroquinolones (like Cipro).

The specific antibiotic that will work best for you will depend on the bacteria in question and your allergy profile.

Risk of Allergic Reaction to Sulfa Drugs

A sulfa allergy is an allergy to drugs with a sulfonamide group as part of their chemical structure. These can be antibiotics, diuretics (water pills), eye drops, topical creams, and other types of drugs.

Sulfa-based antibiotics are commonly used to treat skin, hospital-acquired, and fungal infections. Some researchers estimate that sulfa allergies impact up to 8% of people who use these drugs worldwide.

In some people, sulfa drugs can cause the body to release histamine, causing a systemic (body-wide) inflammatory response that can affect one or more organs.

If you have a sulfa allergy, you should avoid antibiotics such as Bactrim or Septra (TMP/SMX, trimethoprim-sulfamethoxazole). Trimethoprim-sulfamethoxazole is the most commonly used sulfa antibiotic. Because sulfamethoxazole is often combined with trimethoprim, any antibiotic with trimethoprim should be avoided.

People with HIV are at increased risk for experiencing allergic reactions to sulfonamide antimicrobials. Sulfonamide allergic reactions affect 3% to 8% of the general population but are 10 to 20 times more likely in people with HIV.

Sulfa Allergy vs Sulfite Allergy

Sulfa is mostly contained in medications and supplements, whereas sulfites are added as a preservative to many processed foods and occur naturally in fermented foods, including beer and wine.

The symptoms of a sulfite allergy are asthma-like (runny nose, sneezing, watery eyes, and wheezing) as compared to a rash with a sulfa allergy. These are two separate types of allergies with no connection between them.

Symptoms of Sulfa Allergy

Sulfa allergies can present in a multitude of ways, including as a rash. Your reaction may range from mild to severe.

No matter how your allergies present, you should consult a healthcare provider immediately. An initially mild allergic reaction can quickly progress to anaphylaxis, a severe life-threatening reaction requiring emergency medical care.

A generalized flat, red rash, also known as maculopapular eruption, is the most common symptom of a sulfa allergy, but you may also experience the following symptoms:

• Generalized itching (pruritus)

• Hives (urticaria), in which the red, itchy rash develops into raised welts with a clearly defined border

• Swelling of the face, lips, hands, or tongue (angioedema)

• Shortness of breath, which in severe cases may be a sign of anaphylaxis

• Stevens-Johnson syndrome or toxic epidermal necrolysis, which is a blistering rash that destroys the top layers of your skin and mucous membranes

Sun exposure can trigger or worsen your rash. Finding some shade and cooling your body down with ice are some initial steps you can take should you develop a mild skin rash.

Other Side Effects of Sulfa Drugs

Sulfa drugs may also cause other side effects besides an allergic reaction, such as:

• Diarrhea

• Nausea

• Dizziness

• Skin rash

• Headaches

Rare severe side effects include:

• Severe Rash (Stevens-Johnson syndrome or toxic epidermal necrolysis)

• Hepatotoxicity (liver damage)

• Low white blood cell count

• Thrombocytopenia (low platelet count)

• Anemia

Treatment and Prevention of Allergies and Sensitivity

There is no test for a sulfa allergy, so people usually find out that they have an allergy after an adverse medical reaction to a drug, supplement, or personal care product. The diagnosis is made based on your symptoms, physical examination, and medical history.

A sulfa reaction usually resolves within two weeks of stopping the offending medication. Discontinuation soon after the appearance of an itchy rash or hives may lead to a resolution of your symptoms. Antihistamines and corticosteroids may also be prescribed to relieve symptoms.

Some healthcare providers may try a desensitization program for an allergy to sulfa drugs, prescribing small but increasing doses to improve tolerance.

You may be able to take some medications with sulfa that are low-risk. However, be sure to report any known or suspected allergies to a healthcare provider so they can prescribe other types of medications to avoid triggering a reaction.

Summary

Sulfa allergies are usually experienced early after taking medications and typically present as a rash. Once the offending medication is stopped, symptoms usually resolve within two weeks. Antihistamines and corticosteroids can help relieve symptoms in the meantime.

See a healthcare provider if you have a reaction and seek emergency medical care for a severe reaction. Always inform a healthcare provider of a known sulfa allergy to prevent future allergic reactions.

Read the original article on Verywell Health.