It is okay to take Levaquin when you suffer from an allergy to sulfa drugs. Levaquin is not the same kind of drug as sulfa or as penicillin, even though all of the drugs are used as antibiotics. Fluoroquinolone is the base ingredient of Levaquin and fluoroquinolone is a derivative of quinoline (the quinoline has an atom of flourine attached to the C-6 or C-7 position of its central ring) while sulfanilamide is the base of a sulfa drug. Quinoline and fluoroquinolone are synthetic drugs. Fluoroquinolone is used the most for treating pneumonia or bronchitis and they are most often used when other antibiotics fail.