Dr Natasha Bijlani, consultant psychiatrist at the Priory Roehampton, has warned of the dangers of becoming reliant on cheap and readily available sleeping aids and advising insomniacs to seek proper medical help.
It is believed that around six per cent of UK adults suffer from lack of sleep at some time in their lives, which can affect productivity at work, physical co-ordination and social interaction.
Pharmacies stock a cornucopia of various sleep aids, available without prescription and, coupled with the relatively low cost, they are often regarded as 'safe'.
Dr Bijlani explains: "Insomnia is a symptom resulting from a variety of different causes, including depression, ageing, jet lag and serious undiagnosed illness. Any effective treatment needs to tackle the root cause of the problem.
"Over-the-counter (OTC) medications are commonly believed to contain safe dosages of active ingredients and to have a low risk of complications.
"However, many OTC drugs use powerful agents that, if taken in large quantities, could be equal in strength to prescription-only medications.
"The thought of a pill that can solve your sleep problems quickly is very appealing. Unfortunately, sleep medications don't cure insomnia, and they can often make the problem worse in the long run."
Dr Bijlani's concerns about the use of both OTC and prescription sleep medications include:-
- Drug tolerance - taking more and more of the medication for it to work, which can lead to more side effects.
- Drug dependence - relying on the medication to sleep and being unable to sleep without it.
- Withdrawal symptoms - could include nausea, sweating and shaking.
- Side effects - such as drowsiness the next day, confusion, forgetfulness and dry mouth.
- Drug interactions - sleep medications can interact with other drugs, worsening the side effects and can be dangerous with prescription painkillers and other sedatives. Sleeping pills also interact unfavourably with alcohol.
- Rebound insomnia - stopping the medication can sometimes make the insomnia worse.
- Masking an underlying problem - there may be an underlying medical or mental disorder, or even sleep disorder, that if treated would provide more relief from insomnia.
The main ingredient in most OTC sleeping pills is an antihistamine, generally taken for allergies but that also has the effect of making the user feel very sleepy. Some OTC medications also include a pain reliever, which can make them addictive.
The effect of antihistamines on sleep has not been substantiated through research studies according to Dr Bijlani.
She said: "They may have a mild and positive effect on modest short-term insomnia, but side-effects can be blurred vision, constipation, diarrhoea, nausea and vomiting, dry mouth and general dehydration.
"Another class of sleeping pills use the hormone melatonin, which plays a role in regulating the sleep-wake cycle but does not induce sleep per se. Although a prescription-only medication it is easily available through the internet.
"Melatonin has a number of side effects; the more common ones are diarrhoea, abdominal pain and headaches and less frequently reported are nightmares, morning grogginess, fuzziness, nausea, mild depression and low sex drive. Melatonin can also interact unpredictably with other drugs and with no standard recommended dosage, overdosing is easy.
"A number of hypnotic preparations include herbal remedies. One of these commonly used is valerian root, a medicinal herb, which works best if taken regularly for two to three weeks rather than episodically but it has been known to cause liver damage with regular use and should be used with caution."
Dr Bijlani continued: "In general, sleep medications are most effective when used sparingly for short term situations and it is always better to prioritise other solutions such as making changes to behaviour and routine around sleep or to consider psychological interventions such as cognitive behaviour therapy."
"There is not enough evidence to support over-the-counter sleep medications as an effective insomnia treatment. In short, self-treat insomnia with OTC drugs only for short-term sleep difficulties. If you suffer from chronic insomnia, it is advisable to visit your GP, who can refer you for expert help if necessary."