Researchers have created a pill that may put an end to menstrual misery each month, London’s Daily Mail reported.

The pill, known in trials as VA111913, works by bringing down the levels of vasopressin, the hormone that controls the muscles that contract in the uterus. Most other drugs only treat the symptom, rather than the cause, scientists said.

“Dysmenorrhea (painful menstruation) affects a large number of women and there is currently no targeted therapy to treat the condition,” said Dr. Jim Phillips of Vantia Therapeutics, the British company who manufactured the drug.

“I think it would be fair to call it a breakthrough, there is certainly no other treatment like it.”

The first round of trials proved there are very few side effects of the drug, so it will soon move on to a second round of trials in Britain and the U.S.

“We believe this could offer an effective alternative to the over-the-counter painkillers,” Phillips said.

Click here to read more on this story from the Daily Mail.