3 doctors weighed in:

I was diagnosed on Monday with cellulitis at ER, i'm allergic to Keflex but they gave me Bactrim (sulfamethoxazole and trimethoprim) is that a problem. I haven't been feeling good since?

3 doctors weighed in
Dr. John Chiu
Internal Medicine - Allergy & Immunology
2 doctors agree

In brief: Yes

These drugs are unrelated but the sulfur part of Bactrim (sulfamethoxazole and trimethoprim) not uncommonly causes adverse( and allergic )reaction making one feels that he has the flu (drug fever).
Recommend that you contact your doctor immediately to get a substitute. Even if you are allergic to Keflex, you can usually tolerate the 3rd generation cephalosporins (vs Keflex being the 1st generation).

In brief: Yes

These drugs are unrelated but the sulfur part of Bactrim (sulfamethoxazole and trimethoprim) not uncommonly causes adverse( and allergic )reaction making one feels that he has the flu (drug fever).
Recommend that you contact your doctor immediately to get a substitute. Even if you are allergic to Keflex, you can usually tolerate the 3rd generation cephalosporins (vs Keflex being the 1st generation).
Thank
Dr. Al Hegab
Internal Medicine - Allergy & Immunology
1 doctor agrees

In brief: Not a problem

Keflex doesn't cross react with bactrim, (sulfamethoxazole and trimethoprim) you aren't feeling well because of the cellulitis, if the condition isn't improving, see your doctor for re-assessment, wish you wellness

In brief: Not a problem

Keflex doesn't cross react with bactrim, (sulfamethoxazole and trimethoprim) you aren't feeling well because of the cellulitis, if the condition isn't improving, see your doctor for re-assessment, wish you wellness
Thank
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