Modes of awareness associated with use of opium and similar drugs

Used to relieve pain and induce sleep, these substances are also addictive mood-changers. They produce dream-like experiences. The initial use may result in a delightful "high", a delirium with grandiose and sexual hallucinations; but withdrawal sickness is intense, and addicts continue to take the drug more to ward off withdrawal symptoms than to achieve the initial euphoria. These withdrawal symptoms reach a peak between 24 and 48 hours after the last dose. There is rapid desensitization so that dosage levels have to be increased to achieve the same effect; and dependence, both physical and psychological, arises very quickly.