DOES IT WORK?:Chamomile is used for stomach problems, anxiety, insomnia and skin irritations, writes Donal O'Mathuna
CHAMOMILE IS one of the best-known traditional remedies. Used by the ancient Greeks and Egyptians, it also impressed the Anglo-Saxons to the point of being viewed as one of nine sacred herbs given to humans by the god Woden.
Chamomile continues to be one of the best-selling herbal remedies. As a tea, chamomile is used to relieve a variety of stomach and intestinal problems. Its soothing effects on digestion have also been applied to "the nerves" and it has been recommended for anxiety and insomnia. Chamomile is also commonly used in creams as a natural moisturiser and to relieve minor wounds, eczema and skin irritations.
The name chamomile comes from the Greek for "earth apple" derived from the plant's apple-like scent. However, much confusion exists over the naming of a few plants that are called chamomile. The most commonly used medicinal plant is the German, or genuine, chamomile. Roman, or English, chamomile is a completely different plant from a different genus. The two plants have several different scientific names, adding to the confusion. Evidence from studies
Although Roman and German chamomile are used, almost all the available research has been conducted on German chamomile. A number of ingredients have been isolated from the plant and shown to have activities that match the traditional uses.
For example, specific compounds have been shown to relax the intestines, to cause sedation or to have antibacterial and antifungal activity.
These compounds come primarily from the volatile oil, which gives the plant its scent. However, these compounds are not very soluble in water which has important implications for how the remedy is prepared.
Chamomile tea is usually made from the flower heads and will contain mostly the water-soluble compounds. Most of the volatile oil containing the beneficial compounds will evaporate. Making the tea in a closed container is said to capture more of the volatile oil.
Other products are made by soaking the flower heads in alcohol which dissolves a lot more of the water insoluble compounds. These alcohol extracts, or tinctures, are much stronger and have very different effects on the body. They should be used only externally for skin problems.
While chamomile has been used for centuries and the active ingredients studied in lab experiments, very few clinical trials have been conducted.
Research on the oral use of chamomile has been limited to a couple of poor-quality studies with mixed results. More research has been conducted on chamomile creams and ointments used topically.
One study showed that a chamomile cream was slightly better than 0.5 per cent hydrocortisone cream in treating eczema, although the study did not use the best form of double-blinding.
Another study showed that a chamomile mouthwash helped relieve mouth ulcers better than a placebo.
However, another study showed that chamomile cream was not effective in preventing dermatitis caused by cancer radiation therapy.
This suggests that chamomile is not effective with more serious skin problems and should be limited to use with minor skin wounds and irritations.
Problematic aspects
People allergic to plants in the daisy family may also be allergic to chamomile. Products should be tested on the skin before being taken internally.
Chamomile products prepared for external (or topical) use should never be taken orally. Women who are pregnant or breastfeeding should not take chamomile orally. Chamomile has a traditional reputation for causing abortions and some of its compounds have been shown to cause birth defects in animals. Chamomile can also interfere with the absorption of other medications when it relaxes the intestines.
Recommendations
The long traditional use of chamomile has found some support from recent studies. However, this research has primarily been conducted in the lab, and not with people. The topical use of chamomile to relieve minor skin irritation is better supported than its oral use.
While chamomile is relatively safe, certain groups of people should be very cautious when first using it. Check that products have been made from German chamomile rather than Roman chamomile.
Dónal O'Mathúna has a PhD in pharmacy, researching herbal remedies, and an MA in bioethics, and is a senior lecturer in the School of Nursing, Dublin City University