DOES IT WORK? Lavender and insomnia
LAVENDER IS native to the Mediterranean, but widely cultivated in gardens and commercially. Its name comes from the Latin "lavare", meaning to wash, because lavender oil was used to scent public baths in ancient Rome.
Lavender's distinctive odour comes from a volatile oil which today is added to many cosmetic products. The oil contains several components which laboratory tests and animal studies have shown to have a variety of effects.
Attention has centred on their potential sedative effects. This has led to much interest in the use of lavender oil to help people who are agitated, restless or having difficulty sleeping.
Evidence from studies
Lavender flowers or leaves are sometimes used to make a tea, but most of its medicinal reputation has developed from various ways in which the odour is inhaled.
Aromatherapy is possibly the most common way that lavender vapour is administered. Aromatherapy is the systematic use of volatile oils to improve a person's wellbeing.
Many plants produce volatile oils which are believed to have beneficial properties. These can be mixed with other oils and massaged into the skin by an aromatherapist, heated to scent a room, dabbed on clothing or added to a hot bath.
Studies have shown that lavender oil contains components which reduce agitation in animals and can induce sleep. This has led to some interesting, but preliminary studies, of the effects of inhaling lavender in humans.
Most of these studies have been conducted in nursing homes and generally did not have control groups. This is important, because it makes it very difficult to know if the benefits arose from the lavender or some other combination of effects.
For example, an Australian long-term residential home installed lavender oil burners around its facility. When the residents and staff were surveyed, 85 per cent reported that their general wellbeing had improved.
A few other studies have found similar results. However, without control groups it is not possible to know if lavender itself caused the improvements, or if any different aroma would have brought about improvements.
A small number of other studies have found beneficial effects when nursing home residents with severe dementia were exposed to lavender oil aroma. The oil was used when people were given a gentle massage, or put in warm towels used to give bed baths.
Another small study found that adding lavender oil to a vaporiser helped people to sleep better. However, some of these studies did not include comparison groups to determine if the different changes alone would be as beneficial as those with lavender oil.
All of these studies have also been very small, some of them including fewer than 10 people. Taken together, this area of research is showing much promise, but is still at a very preliminary stage.
Problematic aspects
Concentrated lavender oil can cause serious stomach and intestinal cramping if taken orally. Tinctures made from the oil can also cause gastrointestinal problems.
Lavender should not be used along with other sleep-inducing medications or supplements as their effects may be additive. Some people are sensitive to the oil when it is applied to their skin. The effects can get worse with repeated application. Older people may be particularly sensitive to lavender oil applied directly to the skin because of how the skin changes as we age.
Recommendations
Lavender oil is readily available. While the studies to date are small and of relatively poor quality, they consistently point to beneficial effects for those who are agitated or having difficulty sleeping.
For this reason, inhaling lavender through any of the methods mentioned would be worth trying. Care is needed to ensure that the concentrated oil is not ingested or applied to the skin without dilution.
• Dónal OMathúna has a PhD in pharmacy, researching herbal remedies, and an MA in bioethics, and is a Senior Lecturer in the School of Nursing, DCU