Fast Five Quiz: Psilocybin and Other Hallucinogenic Drugs

Richard H. Sinert, DO


September 07, 2021

The onset of psychological effects occurs approximately 30-60 minutes after ingestion of LSD, and they last for approximately 12 hours. Effect peaks at approximately 5 hours. The psychological effects vary both with the individual taking the drug and the physical environment surrounding the user.

Such manifestations as tachycardia, hypothermia, piloerection, hypertension, pupillary dilation, tremor, hypoglycemia, and hyperpyrexia can occur within minutes after oral administration of 0.5-2 µg/kg.

LSD has been found to trigger serotonin syndrome in patients already using precipitating drug combinations (serotonin precursors or agonists, serotonin-release stimulators, SSRIs, nonselective serotonin reuptake inhibitors, nonspecific inhibitors of 5-HT metabolism). Moreover, patients taking SSRIs or lithium have greater potential for LSD-related complications, such as seizures and flashbacks.

Read more clinical information about LSD use.


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