In the right hands, herbal medicine is effective.

Mike Simpson ("Doubts over herbal cures", Mailbox, November 9) is misleading when he says it is doubtful that herbal medicines work and that their effects may be largely placebo or the conditions being treated are self-limiting.

Western herbal medicines prescribed by qualified herbalists such as Hydes Herbal Clinic, are provided in a measured dose within a known active dose range by precise volume of liquid tincture or tablet form.

The chemical components and pharmacological profile of many herbs are known and it is on the basis of this that we prescribe using traditional knowledge alongside the chemical knowledge. Modern Western herbal medicine is based in conventional medical science rather than folklore.

It uses clinical diagnosis, such as listening to your heart or lungs and taking your blood pressure, before prescribing a herbal medicine and the progress is monitored. Practitioners use the knowledge of blood tests and scans before prescribing.

Placebo does not account for PSA (Prostate-Specific Antigen) levels coming down in prostate problems, fibroids shrinking and disappearing, normalising hormonal profiles, cancer markers reducing in the absence of any other treatment, thyroid profiles adjusting to normal in hypo and hyperthyroid problems – these are not self-limiting conditions. Placebo does exist but it is equally at work in both conventional and herbal medicine.

It is short-sighted to believe that only industrially produced chemicals can provide medicines – 80% of the world's population use herbal medicine as their primary healthcare. A substantial number of medicines the doctor uses come from plants; pharmaceutical companies and herbalists are searching for new medicines from plants.

If we allow the Government through EU legislation to destroy the herbalists then you lose a good proportion of this research.

Mr Simpson uses the example of aspirin and willow bark as being chemically the same. They contain different forms of the same chemical and work in a different way. Aspirin (acetylsalicylic acid) works irreversibly through Cox inflammatory pathway while salicylic acid in willow does not.

When you see a qualified herbalist the precise required dose of willow is known; you get a quantified prescription, not a random dose.

It is important to take advice from a qualified medical herbalist in just the same way as it is important to take a doctor's advice before taking conventional medicine.

Qualified medical herbalists use known concentrations of herbal medicines of herbs which are specific for medical conditions.

At Hydes we also work jointly with many GPs and hospital consultants to introduce herbs to reduce the dose of stronger conventional medicines, such as cyclosporine and steroids in eczema, steroids in ulcerative colitis, azathioprine in autoimmune conditions. This integrated medical approach aims to benefit the patient and keep the maximum therapeutic effect while reducing the impact of side effects consequent upon the use of many of our stronger conventional drugs.

In the region of three million people in the UK today use or have used herbal medicines. Even if you don't need it right now, do not let the Government take away your right to choose it in the future.

Dr Serene Foster, principal practitioner, immunologist and medical herbalist, Hydes Herbal Clinic.