The TGA is working toward reforms to help Australians make informed choices about complementary medicines, as experts question their efficacy.

Vitamins are useful for treating specific deficiencies but most Australians who use multivitamins just have very expensive urine, Australian Medical Association President Michael Gannon says.

Seven out of every ten Australians take some form of vitamin or supplement but experts have questioned their efficacy and the shelf space they dominate in pharmacies.

Adjunct Associate Professor Ken Harvey from the Department of Epidemiology & Preventive Medicine at Monash University told the ABC's Four Corners program there's little evidence to suggest multivitamins actually work.

Buying multivitamins benefits the companies that manufacture them by boosting profits but for the average Australian multivitamins provide "no benefit".

"What you need is a good diet, you're pissing the money down the toilet for no benefit," he told the program.

However, the Australian Self Medication Industry says complementary medicines are useful because many Australians have poor diets.

"Vitamin and mineral supplements can play an important role for the 52 per cent of Australian adults who do not eat the recommended intake of fruit or the 92 per cent who do not eat the recommended intake of vegetables each day," the ASMI said in a statement.

A recent investigation by consumer group CHOICE found one in three Australian pharmacists recommended alternative medicines to treat stress.

Nearly half, 46 per cent, recommended products containing a mixture of B vitamins and possibly other vitamins, minerals and herbs.

Twenty-six per cent recommended Bach flower remedies to treat stress and about eight per cent recommended magnesium supplements.

The AMA is concerned that many of these homeopathic products, like Bach flower, are given legitimacy, despite a lack of evidence showing they work, simply because they are sold in a pharmacy.

It's known folate plays an important role during pregnancy and iron supplements are prescribed for those who are anaemic, but most doctors consider multivitamins a waste of money.

"What a lot of Australians have is very expensive urine," Dr Gannon said.

The Therapeutic Goods Administration is pushing for reform which would create a new class of evidence-based complementary medicines. This would mean products would carry some form of indication that the product had been tested for safety and efficacy.

"The new reforms will support Australian consumers make informed choices about the use of complementary medicines and help protect consumers from potentially misleading therapeutic claims," the TGA said in a statement to AAP on Tuesday.