Herbalists have warned people are putting their health at risk by using remedies inappropriately.

The UK market for herbal remedies such as St John's Wort and ginseng is worth around �126m a year, but experts say some of that is money badly spent.

Trudy Norris, president of the National Institute of Medical Herbalists warned against mixing remedies, combining them with conventional medicines or taking poor quality supplements.

Commonly used herbs

Ginseng - helps nerves and stress Ginko - circulation Echinacea - boosts immune system Vitex Agnus Castus - balancing hormone levels St John's Wort - for mild depression but should not be combined with conventional drugs

She told BBC News Online herbs were safe and could be used successfully.

But she added:" What we are concerned about is that lots of people self-prescribe in an inappropriate way.

"So someone may want to use a herb instead of a drug, for example someone may buy a herbal combination and equate it with HRT, and they don't equate.

"And they may go into a shop to buy, say, St John's Wort, where there's a whole shelf-full of various quality and standards."

Self-medication

She said people also did not know supplements could interact with conventional medicines.

Herbs can sometimes cause more harm than good

Trudy Norris, National Institute of Medical Herbalists

She highlighted research which showed 60% of people buying remedies had taken them while they were also taking conventional medicines.

"We still get calls from people taking St John's Wort saying 'it doesn't affect the contraceptive pill does it?' Well it does," she said.

Speaking at the beginning of Herbal Medicine Awareness Week, Ms Norris added: "There are some obvious limitations to buying over-the-counter remedies, since herbs can sometimes cause more harm than good if used inappropriately, just like other medicines.

"We are not against commercial herbal remedies bought for self-medication, but urge people to find out as much as possible before self-prescribing.

"This is particularly important if you are pregnant, taking any other form of medication or taking over-the-counter remedies for anything other than a minor ailments.

She warned said: "In the market place matters of health and illness can create vulnerability.

"The practitioner's main focus is the actual health needs of the patients over and above any consideration of profit.

"This can not always be said of the entire supplement market."

EU ruling

Analysis of some products, particularly Chinese remedies, has shown they contain steroids and toxic heavy metals.

The Medicines Control Agency (MCA) has expressed concerns over some herbal remedies including Kava-kava, which it is considering banning after some patients reported liver problems.

Ms Norris welcomed the traditional herbal medicines directive being considered by the European Union, which she said would go some way to addressing confusion about over-the-counter remedies.

It will look at information, labelling and quality.