Researchers from the University of Zurich are suggesting that a dose of the stress hormone cortisol may help people overcome phobias.
They have come up with a pill which is based on cortisol. Cortisol impairs the retrieval of memories, and people forget what they are fearful of.
Working on this principle the researchers were curious to see if people with a phobia such as fear of spiders, when given a dose of the hormone before exposure to a spider, or their own personal phobia trigger, would be helped.
Arachnophobia a fear of spiders affects as many as 7.5 million Britons, and scores of others have an irrational fear of something, heights, public speaking, getting in lifts etc. In many the phobia can affect everyday living.
The Swiss researchers tested the theory on 40 people with social phobia and 20 with spider phobia.
Half of the group were given cortisol and the rest a placebo version and depending on their phobia they were then asked to give a speech in public, or were exposed to a spider.
The researchers found that the subjects who received the hormone reported less stimulus-induced fear and anxiety.
The tests also found that a fortnight's course of cortisol was enough to reduce people's fear of spiders by half and the scientists believe further treatment, combined with counselling, could completely banish the phobia.
The spider phobics were made to look at a colour photograph of a large spider and were then asked to gauge how scared they were, on a scale of one to ten; the researchers watched for outward signs of acute fear such as sweating or trembling.
This procedure was carried out six times over the course of two weeks.
It was found that those taking the cortisol were noticeably less fearful than the others and by the fourth treatment their fear levels had dropped by 45 per cent.
More importantly the effects appeared to last, with the volunteers still feeling brave two days after their last cortisol pill.
A second group with a fear of public speaking, one of the most common phobias in the UK, produced a similar result.
The men and women were given cortisol before making a speech in front of an audience and their heart rate remained much steadier and their levels of fear dropped considerably.
Those patients who were not given the hormone treatment who reported the least anxiety released the most cortisol, which the researchers say supports their theory.
The team, led by Dr. Dominique de Quervain, suggest that cortisol treatment, in conjunction with behavioural therapy, could be used to reduce or even extinguish phobias and post-traumatic stress disorders which are triggered by a particular stimulus.
They believe that the hormone, released naturally during stress, works by making people forget what they are scared of; it is thought that cortisol cuts blood flow to the part of the brain that retrieves memories - leaving people unable to remember their phobia.
The hormone also boosts the formation of new memories which means that people treated with it retain information about their new-found bravery over images of their previous fear.
Experts have welcomed the research but warn that it is still at a very early stage.
Phobia expert Dr. Cosmo Hallstrom, a fellow of the Royal College of Psychiatrists, says cortisol is the hormone released during stress and it is a powerful drug.
He says care must ensure that the treatment is not as bad as the condition.
Hallstrom says the treatment would not help people stop avoiding the thing they had a phobia of.
Current phobia treatments involve therapies such as cognitive behavioural treatment, in which sufferers are made to confront their phobia, and the use of anti- depressant drugs and tranquillisers such as Valium to alleviate anxiety.
The National Phobics Society, says all research into treatment possibilities is welcome, but as phobias have a strong behavioural component they view this particular treatment as something that could be used to complement other psychological interventions such as cognitive behavioural therapy.
The research is published in the journal Proceedings of the National Academy of Sciences.