A new study by Professor Charlie Xue of RMIT University and his colleagues is the first study of its kind to show how people use herbal medicines.
Professor Xue says previous studies have shown a marked increase in the use of herbal medicines by Australians and his survey of 2,526 people in Victoria on their use of the 24 most common medicinal herbs in Australia found that 22.6% of participants had used at least one of the herbs in the past 12 months.
The highest use was among 35 to 54 year-olds who were university-trained, and those who earned between A$60,000 and A$80,000 per year and aloe vera, garlic and green tea were the most popular herbs, each used by about 10% of participants.
Other popular herbs included echinancea, ginger, peppermint, ginseng, gingko biloba, evening primrose, dandelion and St John's wort.
The study revealed that more than 90% of people felt their herbal medicine had been helpful in enhancing their general health and well being, or providing relief from specific medical conditions and Professor Xue says that is quite important from a clinical perspective.
Professor Xue says many people sought herbal help for chronic conditions, with the most common being skin problems, sleep disorder, anxiety, stomach, cold, flu and fever, however less than half of the study participants were aware of the potential harm from herbal medicine.
The study found more women than men use herbal medicines, with 14.4% of women taking herbs while they were pregnant, and 10% while breast feeding and more than 50% of participants had also used drugs at the same times as herbs for the same medical condition.
The study found people who take herbal medicine are often unaware of the scientific evidence on its effectiveness and safety - some herbs such as St John's wort are known to interact negatively with some pharmaceuticals - and many rely on recommendations from others, including the internet, friends and family.
Only 8% of users were recommended to take herbal medicines by their GPs and Professor Xue says this is not surprising.
Most surveyed said they would accept the advice of their medical practitioner on whether to use herbal medicine but only 50% of people had discussed their use of herbal medicines with their GP.
Xue says this may be because many doctors don't have enough knowledge about herbal medicines and he suggests better general knowledge might generate discussion with patients about their use of herbal medicines.
Professor Xue says the lack of good quality evidence on the effectiveness and safety of herbal medicines remains an issue and he says more research needs to be done.
He says for many doctors it is a dilemma because there is not enough data for them to give informed advice and recommendations.
Professor Xue says in addition to health enhancement, specific herbs are commonly used to treat a range of medical conditions, without clear evidence of efficacy and concurrent use of herbal and conventional medicine is relatively common and the majority of herbal medicine users are not aware of potential adverse effects.
The research is published in the current issue of the journal Pharmacoepidemiology and Drug Safety.
