Washington, July 30 (Reuters): A new pill that aims to keep alcoholics from drinking again after they have quit could hit the shelves by the end of this year, after US health officials approved the drug yesterday.

The drug, called Campral, may not work for people who are actively drinking when they start taking the pill or who are abusing other substances, the US Food and Drug Administration (FDA) said in a statement.

It was not clear how the pill worked, health officials said, but studies showed that more patients who took the drug stayed away from drinking compared to those who took a placebo.

“While its mechanism of action is not fully understood, Campral is thought to act on the brain pathways related to alcohol abuse,” the FDA wrote.

Lipha Pharmaceuticals, a subsidiary of German drug maker Merck KGaA, makes the drug, generically known as acamprosate.

Forest Laboratories Inc. owns the licensing rights to market the drug in the US and plans to start selling it later this year, the company’s president and chief operating officer Kenneth Goodman said in an interview.

Common side effects from Campral, which has been widely used in Europe for 15 years, include diarrhoea, nausea, vomiting and abdominal pain.