A new  drug to treat urge incontinence has side effects including increased blood pressure that need to be considered when weighing whether the medicine should be approved, U.S. regulators said.

The medicine, mirabegron, also increased heart rate and was associated with hypersensitivity reactions ranging from painful rash to anemia, the Food and Drug Administration said today in a report..

“Although the safety results from the clinical trials database appear generally reasonable, the special safety concerns, especially the increases in blood pressure and pulse” need additional consideration, FDA staff wrote.

The drug reduced the number of times patients were incontinent, or involuntarily urinated, in a 24-hour period, the staff wrote.

Mirabegron eliminated baseline incontinence in 32 percent of patients taking 50 milligrams and reduced incidents of incontinence by half in 54 percent of those in final-phase studies of 862 patients taking the medicine, compared to 878 people on placebo.

The treatment also was linked to tests revealing potential liver disease, a small number of urinary tract infections and malignant tumors, FDA staff wrote. The reason mirabegron would lead to tumor formation is unknown.

Drugs on the market to treat urge incontinence block a receptor that causes contractions that make someone feel the urge to urinate though they also can affect the ability to empty the bladder, Mirabegron enhances bladder storage without affecting patients’ ability to urinate.