Kristensen F W
Ugeskr Laeger. 1994 May 9;156(19):2875-8, 2881.
Patients with the combination of cannabis abuse and psychosis are difficult to treat. The intoxicated state has many similarities to schizophrenia. Like other drugs with abuse potential cannabis affects the brain's reward system. It has not been possible to show major structural changes in the cerebrum, but by electron microscopy structural changes can be shown in animals especially in the hippocampus. The drug is taken in order to escape reality, and a vicious circle tending to maintain the person's abuse pattern which includes reduced energy, judgment and memory may be established. Cannabis may cause toxic psychosis, with a tendency to recurrent psychoses with continued abuse. There is no convincing support for the assumption that cannabis can cause chronic functional psychosis following cessation of abuse. Schizophrenic patients who use cannabis are often trying to reduce the discomfort caused by symptoms in the prodromal phase. By continued abuse positive psychotic symptoms are worsened. Antidepressant drugs may diminish the depressive elements of the disease. Some cannabis users are especially sensitive and develop toxic psychosis. Patients with repeated toxic psychosis may erroneously be diagnosed as schizophrenics. It is therefore important to be aware that a psychotic state may be caused by abuse of cannabis, and adjust treatment to this fact.
同时患有大麻滥用和精神病的患者很难治疗。中毒状态与精神分裂症有许多相似之处。与其他具有滥用潜力的药物一样，大麻会影响大脑的奖赏系统。虽然尚未发现大脑有明显的结构变化，但通过电子显微镜可以在动物身上，尤其是在海马体中显示出结构变化。吸食大麻是为了逃避现实，这样可能会形成一个恶性循环，导致患者维持包括精力减退、判断力和记忆力下降在内的滥用模式。大麻可能会导致中毒性精神病，持续滥用会有复发精神病的倾向。没有令人信服的证据支持大麻在停止滥用后会导致慢性功能性精神病这一假设。使用大麻的精神分裂症患者常常试图减轻前驱期症状带来的不适。持续滥用会使阳性精神病性症状恶化。抗抑郁药物可能会减轻该病的抑郁症状。一些大麻使用者特别敏感，会发展为中毒性精神病。反复出现中毒性精神病的患者可能会被误诊为精神分裂症患者。因此，重要的是要意识到精神病状态可能是由大麻滥用引起的，并据此调整治疗方案。
