Macrobid (generic: nitrofurantoin monohydrate/macrocrystalline) is a prescription medication used to treat urinary tract infections. Macrobid belongs to a group of drugs called nitrofuran antiobiotics. These work by stopping the growth of bacteria.

This medication comes in capsule form and is taken 2 times a day with food.

Common side effects of Macrobid include diarrhea, stomach upset, dizziness, and drowsiness. Do not drive or operate heavy machinery until you know how Macrobid affects you.