Shampooing with a drug designed to treat brittle bones could help cure baldness within days, research suggests.

Scientists found the therapy promotes speedy sprouting of hair in lab tests.

It works by blocking a naturally occurring protein that kills off growth and plays a key role in male baldness.

Experts are “optimistic” the treatment, known as WAY-316606, could one day help millions of men.

Researchers found the drug, originally developed for osteoporosis, boosted growth from human hair follicles in just two days.

They now hope to carry out clinical trials on men with thinning patches.

Lead researcher Dr. Nathan Hawkshaw, from Manchester University, said: “The fact this new agent, which had never even been considered in a hair loss context, promotes human hair growth is exciting because of its translational potential: it could one day make a real difference to people who suffer from hair loss. I’m very optimistic it could work.

"In lab tests, the drug started promoting growth in hair follicles in just two days — that’s pretty quick," he noted.

“We are looking at using it as a topical treatment, a gel or shampoo, that could reach the follicle.”

Hawkshaw said there are no known side effects of the bone drug.

This story originally appeared in The Sun.