Sulfa Drugs Side Effects

Sulfa drugs or sulfonamides are drugs used to treat bacterial and fungal infections. Prontosil was the first sulfa drug discovered by German physician Gerhard Domagk in 1935. Though not known to kill bacteria, sulfa drugs inhibit their growth and help in treatment of bacterial infections. There are several known side effects of sulfa drugs, but in spite of the side effects, it is still used for the treatment of some form of malaria, urinary tract infection, ear infection, bacterial meningitis and many other infections. Sulfisoxazole (Gantrisin) and combination drug sulfamethoxazole and trimethoprim (Bactrim, Cotrim) are the most common types of sulfonamides. These are available in liquid form or as tablets for oral and topical use. Septra, Pediazole and Bactrim are the most common sulfa drugs available today.

Side Effects of Sulfa Drugs

There are various side effects of sulfa antibiotics as well as non-antibiotic sulfonamides. Antibiotic sulfa drugs differ structurally from the non-antibiotic sulfa drugs, and the antibiotic form is said to more likely cause side effects. Sulfadiazine and sulfamethoxazole are the members of sulfonamides group that are used as antibiotics. Though most of the symptoms of the side effects goes away within few days, you should always see a physician if the condition worsens. These are the side effects of the drugs and the reasons for decrease in its use:

Allergies
Sulfa allergy is a very common side effect of other drug reaction to sulfa drugs. People with lower immunity fall into the category of those at risk from sulfa drugs allergy. Common sulfa allergy symptoms are skin reactions leading to hives and rashes. In severe cases even face, tongue and lips swelling becomes visible. It might also lead to anaphylaxis, where the throat swelling makes breathing and swallowing difficult, and this condition needs immediate medical help.

Skin Sensitivity
Another common side effects associated with the sulfa drugs is the increase in the skin sensitivity to light. This leads to easy skin sunburn and people experiencing this side effect are often recommended to wear protective clothing and sunscreen to avoid direct sunlight.

Neurological Side Effects
Though not very severe, some people taking sulfa drugs also complain of headache, drowsiness and dizziness. In severe cases, even fainting and hallucinations have been noticed and hence, intake of these drugs should be immediately discontinued.

Gastrointestinal Side Effects
Most of the gastrointestinal side effects caused due to sulfa drugs disappear after discontinuation of the drug. The common gastrointestinal conditions resulting due to the use of sulfa drugs are, diarrhea, nausea, gas in abdomen, vomiting and loss of appetite.

Liver Injury
Sulfa drugs also have the potential to cause injury and damage to liver. This liver injury symptoms include jaundice, dark urine where the patient becomes highly susceptible to bleeding and bruising.

Kidney Injury
Upon interaction with certain antibiotics, sulfa drugs are said to cause damage to the kidneys. This further leads to conditions like painful and difficult urination, sometimes with traces of blood. Kidney damage could also sometimes lead to flank pain.

Muscle and Body Ache
Another rare sulfa drugs side effect is myalgia. Myalgia occurs usually due to viral infection, but could also result from sulfa drugs reaction. This causes the muscles and bones to ache and feel sore. This aggravates the condition further leading to severe joint pains.

Stevens-Johnson Syndrome
Stevens-Johnson Syndrome is considered one of the most dangerous side effects of sulfa drugs. Purple or red blisters appear all over the body that leads to shedding of skin on the affected area, and makes the skin susceptible to bacterial infections. Patients who have been taking sulfa drugs should immediately see a doctor upon noticing purple blisters on the skin.

Other Drug Interactions with Sulfa Drugs

There are many medicines which might have interactions with sulfa drugs. Interaction with other drugs increases the risk of side effects from these drugs. Hence, precautions are taken by a physician while prescribing medicines along with sulfa drugs. These are some drugs that have higher possibility of interaction with sulfa drugs:

• Birth Control Pills
• Acetaminophen (Tylenol)
• Hyperactive thyroid drugs
• Anticoagulant warfarin (Coumadin)
• Anti-diabetic drugs glyburide (Micronase)
• Anticancer drug methotrexate (Rheumatrex)
• Drug for alcohol abuse alcohol disulfiram (Antabuse)
• Antiseizure drug valproic acid (Depakote, Depakene)
• Diuretic Drug Hydrochlorothiazide (HCTZ, HydroDIURIL)

Use of sulfa drugs can be limited, but cannot be stopped. Hence, it is important to take precautions to avoid sulfa drugs side effects. Always consult a doctor before taking any drugs if you suffer from allergies, asthma, kidney and liver diseases. It is also advisable for breastfeeding mothers and pregnant ladies to avoid sulfa drugs as far as possible.