There are no diagnostic tests for sulfa allergy. However, sulfa desensitization might be an option, especially if medication containing sulfamethoxazole is needed. However, sulfa desensitization might be an option, especially if medication containing sulfamethoxazole is needed. Sorry to read of your problem. Macrobid is a relatively safe antibiotic provided you do not have a allergy to the medication. If your urgency is related to an infection, the antibiotic may help. How to use Macrobid. Take this medication by mouth with food as directed by your doctor, usually twice daily (every 12 hours). Swallow the medication whole for best results. TMP-SMX has been the standard therapy for UTIs; patients with a sulfa allergy can take trimethoprim alone and achieve a similar cure rate. Side effects include skin rash, nausea, and vomiting. Doctors give unbiased, trusted information on whether Macrobid can cause or treat Allergies: Dr. Carter on macrobid sulfa allergy: It is certainly possible. Doctors give unbiased, trusted information on whether Macrobid can cause or treat Allergies: Dr. Carter on macrobid sulfa allergy: It is certainly possible. Nitrofurantoin antibiotic is very often used to treat urinary tract infections. Allergic reactions to this is rather uncommon. However, when it happens the skin reactions could show up as itching, swelling of skin, eczema, and even serious conditions such as stevens-johnson syndrome. Other symptoms affecting gastrointestinal , urinary, blood. I must have take tons of macrobid, sulfa, the pills that make you pee orange and the ones that make you pee green, and some other forgotten antibiotics. I was not chancing loosing my kidneys, I would rather chance relapse. OBJECTIVE. To present an approach to use of sulfonamide-based (sulfa) medications for patients with sulfa allergy and to explore whether sulfa medications are contraindicated for patients who require them but are allergic to them. I am allergic to sulfur antibotics so my Doctor prescribed Nitrofurantoin for a UTI. Everyone should read the prescriptions that will interfer or have a reaction to this drug. Macrobid (nitrofurantoin) is an antibiotic that fights bacteria in the body. Macrobid is used to treat urinary tract infections. Macrobid may also be used for purposes not listed in this medication guide.