Fever and chills caused by nitrofurantoin taken after sexual intercourse.

Nitrofurantoin is one of many antibiotics used in the treatment of urinary tract infections (UTI). The drug is also used for the prevention of recurrent UTI in women. We report a case of nitrofurantoin drug fever associated with its use, following sexual intercourse, for chemoprophylaxis of UTI. The intermittent appearance of the side effects due to the occasional use of antibiotics, such as in this case, may easily lead to misdiagnosis.