Olanzapine belongs to the antipsychotic class of drugs. If an overdose of olanzapine leads to collective poisoning, the patient needs to be treated quickly at a hospital. First of all, the patient should be given a thorough gastric lavage, and the lavage solution should be warm water or saline, which can usually be instilled in parts. If the patient is unconscious, it is recommended to apply mechanical gastric lavage by intubating the stomach with a gastric lavage machine. After gastric lavage, diarrhea can be induced by mannitol enema or activated charcoal infusion in the intestinal cavity for adsorption, after which diuretic treatment can be given, such as applying hydrochlorothiazide or furosemide for diuresis. Symptomatic antidotes, such as flumazenil intravenously, can also be applied. If the patient has severe hepatic or renal failure, continuous blood purification can be used to give detoxification, but the preferred method is to apply hemoperfusion.