Symptoms of an allergic reaction to sulfa drugs include hives, decreased blood pressure and swelling of the mouth, face, throat and tongue, according to Healthline. Another symptom of sulfa drug reaction is anaphylaxis, which is a potentially life-threatening reaction that must be evaluated immediately by a medical professional. Although rare, symptoms similar to serum sickness may occur after 10 days of sulfa drug treatment, characterized by swollen lymph nodes, drug-induced arthritis, hives, skin eruptions and fever.
People who are sensitive to sulfa should avoid certain medications, according to Healthline. Those with sulfa sensitivity should not take combined antibiotic medications, such as Bactrim or Septra, or sulfasalazine, which is a treatment for rheumatoid arthritis, ulcerative colitis and Chron's disease. They should also not take Dapsone, which is used in treating some types of pneumonia, dermatitis and leprosy.
Even with sulfa sensitivity, not all drugs containing sulfonamides are prohibited, notes Healthline. Many can still take diabetes medications, such as Amaryl, Diabeta and Glynase, and the nonsteroidal anti-inflammatory drug Celebrex. They may also be able to take Dosepro, Sumavel and Imitrex, medicines used for treating migraine and diuretics such as Lasix and Microzide.
Around 3 percent of people have sulfa drug allergies. Sulfa drugs first came into use in the 1930s to treat bacterial infections.