UPDATE 1-US FDA clears Schwarz Pharma, Pfizer bladder drug

(Adds details on how drug works, side effects)

WASHINGTON, Oct 31 (Reuters) - A new drug made by Schwarz Pharma SRZG.DE to treat patients with overactive bladders won approval from U.S. health officials on Friday.

The drug, Toviaz, is manufactured by Germany's Schwarz Pharma and distributed by Pfizer Inc (PFE.N) of New York.

Toviaz works by relaxing the smooth muscle tissue of the bladder to reduce urinary frequency and leakage of urine, a Food and Drug Administration statement said. The drug is approved for adults only.

Common side effects include dry mouth and constipation, the agency said. Dry eyes and trouble emptying the bladder were reported less frequently.

Some people should not use the drug, including patients with severe liver impairment or uncontrolled, narrow-angle glaucoma, the FDA said.

The drug's generic name is fesoterodine fumarate. (Reporting by Lisa Richwine, editing by Leslie Gevirtz and Gerald E. McCormick)