1 doctor weighed in:

Is it safe to take sulfa drugs if i'm allergic to thimerosal?

1 doctor weighed in
Dr. Carla Enriquez
Pediatrics

In brief: Yes

Thimerosal is a mercury based preservative.
Sulfas are sulfonamide based antibiotics. The two don't cross react, but thimerosal may be used as a preservative in topical solutions of antibiotics, including sulfas. If a person has an allergic reaction to a compound with both ingredients, then the doctor has the task of deciding which or both caused the reaction. But this would be quite unusual.

In brief: Yes

Thimerosal is a mercury based preservative.
Sulfas are sulfonamide based antibiotics. The two don't cross react, but thimerosal may be used as a preservative in topical solutions of antibiotics, including sulfas. If a person has an allergic reaction to a compound with both ingredients, then the doctor has the task of deciding which or both caused the reaction. But this would be quite unusual.
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