"Psilocybin the psychedelic compound in magic mushrooms may one day be an effective treatment for patients with severe depression who fail to recover using other therapies scientists said on Tuesday.  Mushrooms grow at the Highline Mushrooms farm Canadas largest mushroom grower in Leamington Ontario Canada April  . REUTERSMark Blinch A smallscale pilot study of psilocybins use in cases of treatmentresistant depression showed it was safe and effective the British researchers said.  Of  patients given the drug all showed some decrease in symptoms of depression for at least three weeks. Seven continued to show a positive response at three months. Five remained in remission beyond the three months.  Robin CarhartHarris who led the study at Imperial College Londons department of medicine said the results published in the Lancet Psychiatry journal were striking.  Many patients described a profound experience he said and appeared to undergo a shift in the way they perceived the world.  But we shouldnt get carried away with these results he told reporters at a briefing in London. This isnt a magic bullet. Were just learning how to do this treatment.  Magic mushrooms grow worldwide and have been used since ancient times both for recreation and for religious rites.  British researchers led by David Nutt a professor of neuropsychopharmacology at Imperial have been exploring the potential of psilocybin to ease severe forms of depression in people who dont respond to other treatments.  The World Health Organization estimates that some  million people worldwide are affected by depression a common mental disorder characterized by sadness loss of interest or pleasure tiredness feelings of guilt or low selfworth disturbed sleep and appetite and poor concentration.  Many patients respond to treatment with anti depressants and cognitive behavioral therapy but around  percent dont get better and are classed as having treatmentresistant depression.  Psilocybin acts on the serotonin system suggesting it could be developed for treating depression. But hallucinogenic drugs can also cause unpleasant reactions including anxiety and paranoia so Nutts team wanted to find out if psilocybin can be given safely.  The trial involved six men and six women aged between  and  all diagnosed with treatmentresistant depression. They all went through a full screening process before being allowed to participate and they were fully supported before during and after they received psilocybin.  The patients were given psilocybin capsules during two dosing sessions seven days apart.  Pappardelle Magic Mushroom Truffles prepared by chef Harlan Goldstein is shown at Gold restaurant in Hong Kong March  . REUTERSAndy Ho Blood pressure heart rate and the selfreported intensity of the effects of psilocybin were monitored during each session and the patients were seen by a psychiatrist the next day and one two three and five weeks after the second dose.  CarhartHarris said no serious side effects were reported during the study although all volunteers said they were slightly anxious before and during initial drug administration.  Psychedelic drugs have potent psychological effects and are only given in our research when appropriate safeguards are in place he said. I wouldnt want members of the public thinking they can treat their own depressions by picking their own magic mushrooms. That kind of approach could be risky.  Nutt said the results showed that psilocybin is safe and fast acting so may  if administered carefully  have value for these patients.  Reporting by Kate Kelland editing by Larry King Our StandardsThe Thomson Reuters Trust Principles. httpthomsonreuters.comenaboutustrustprinciples.html"