Do not take this medicine with any of the following medications:
-sulfa drugs

This medicine may also interact with the following medications:
-acetazolamide
-antacids
-methazolamide
-sodium bicarbonate

They need to know if you have any of these conditions:
-dehydrated
-kidney disease
-liver disease
-an unusual or allergic reaction to methenamine, tartrazine dye, other medicines, foods, dyes, or preservatives
-pregnant or trying to get pregnant
-breast-feeding

Tell your doctor or health care professional if your symptoms do not improve or if you get new symptoms.

You will need to be on a special diet while taking this medicine. Ask your health care professional how many glasses of water or other fluids to drink each day. Also, ask which foods to include and which to avoid to help keep your urine acidic. Your urine must be acidic for this medicine to work.

Keep out of the reach of children.

Store between 15 and 30 degrees C (59 and 86 degrees F). Keep container tightly closed. Throw away any unused medicine after the expiration date.