Petrol or clonazepam will only help in controlling the symptoms. For an overall improvement it is useful to have other non habit forming medication as well as psychotherapy. A comprehensive treatment plan will benefit him and those around him. You can choose a psychiatrist based on your area of residence. Hope this helps you.. Leaving your friend untreated is going to worsen his condition, and also be mindful of him developing petrol dependence... Seek help at the earliest..