The power of plants
Nature plays a huge part in medicine says Dr Rosemary Leonard, but some herbal remedies are more effective than others
Medicines derived from plants have been used for centuries to relieve all kinds of ailments. Even today, several conventional medicines in use are plant-based. The heart drug digoxin comes from foxgloves, and atropine, used to dry secretions and to widen the pupil in the eye, from deadly nightshade. More recently, the chemotherapy drug taxol, originally sourced from yew trees, has proved effective against a number of cancers. But the biggest range of medicinal plant extracts is sold as herbal or ‘alternative’ remedies. Until recently there was no way to gauge how good the products were, but now things have changed for the better. Historically there were only a few herbal medicines to have product licences just like standard medicines, and the majority were classified as food supplements. So most had to meet food safety regulations, but not go through the strict testing and controls required for regular medicines. This resulted in a wide variation in quality and safety and, because they were not classed as standard medicines, health claims or information about possible side effects were not allowed on the packaging.
On the register
A new system of registering traditional herbal remedies has now been introduced by the UK’s medicines licensing authority. Herbal products registered under the scheme are guaranteed to be of pharmaceutical quality, just like standard medicines.
- This means they meet specific safety and quality standards.
- Content of active ingredients is carefully controlled.
- They can make appropriate, approved health claims, and so include a product information leaflet with warnings about possible side effects.
One important difference from standard medicines is the proof of effectiveness. Rather than going through extensive clinical trials, registered traditional herbal products have only to have been in use for at least 30 years. This does not mean that they are effective.
However, many go through trials providing evidence of their benefits. These would not be sufficient for them to get a standard medicines licence, but the scheme does mean that consumers have access to a favourite remedy with a guarantee of safety and quality. Since the scheme began last year, 21 products have received a licence – check the packaging for a Traditional Herbal Registration (THR) number.
What's the remedy?
These are the herbal remedies that my patients use most:
St John’s wort – found in several clinical trials to be effective for mild depression. It usually has to be taken continuously for two to three weeks to take effect. It should not be taken with other anti-depressants, and can cause a dry mouth, dizziness, tiredness and increased sensitivity to sunlight. It can also reduce the effectiveness of some drugs, including the contraceptive pill. Several licensed St John’s wort products are available.
Feverfew is used as a migraine preventative – some of my patients have reported that after taking 250mg regularly every day, their migraines have gradually become less frequent and severe.
Agnus Castus is a popular remedy for premenstrual syndrome. It may help balance levels of the hormones oestrogen and progesterone. It should not be used with other treatments, such as the pill.
Devil’s Claw root is thought to have anti-inflammatory properties, and is used to treat painful joints and muscles, and backache. It can be taken with other painkillers, but should be avoided by those who have stomach problems, particularly indigestion, ulcers or
acid reflux.
Valerian has sedative properties – low doses may relieve anxiety; larger doses for sleep disturbances. Pelargonium extract has been shown to have antiviral and anti-bacterial actions. Research suggests it can help support the system in recovering from coughs, colds and sore throats – for age six and over.