Common sleeping aid melatonin could soon be available at chemist without a prescription

A common medication used to treat insomnia could soon be available over the counter at pharmacies.

High-dose melatonin tablets are currently only available on prescription, while some homeopathic varieties can be bought at chemists.

However, the move by the Therapeutic Goods Administration to make the stronger pills more easily accessible has health experts divided.

"This presents a safer alternative to patients who are suffering from insomnia," Chris Freeman from the Pharmaceutical Society of Australia told 9News.

"Pharmacists are medicines experts and have a deep knowledge of medicines, and can be trusted to supply it," Mr Freeman said.

However, sleep specialists who haven't been consulted oppose the plan.

"I'm disappointed in a way this is happening so quickly," Professor Ron Grunstein from the Woolcock Institute said.

"There's some studies that suggest it worsens diabetic control, you wouldn't use it on pregnant women or breastfeeding women."

The NSW Poisons Information Centre made a submission to the TGA saying the number of calls regarding melatonin has increased dramatically over the past six years, especially mishaps relating to children.

The changes are planned for October, with possible restrictions on age and pack sizes.