Pyretogenic effect of lysergic acid diethylamide

This early (1954) animal study (n=9) investigated the pyrogenic (fever-inducing) properties of LSD (50μg/kg), which produced a rise in body temperature of normal rabbits, cats, and dogs. This rise in temperature which lasted up to 9 hours is antagonized by the administration of sodium pentobarbital but not by antipyrine or adrenergic blocking agents.

Abstract

From the conclusion: “Lysergic acid diethylamide produces a rise in body temperature of normal rabbits, cats, and dogs. This rise in temperature is antagonized by the administration of sodium pentobarbital but not by antipyrine or adrenergic blocking agents”

Authors: Akira Horita & James M. Dille

Summary

Akira Horita and James M. DiHe Department of Pharmacology, School of Medicine, University of Washington, Seattle

LSD exhibits little or none of these actions, but rather a hallucinogenic effect. It increases body temperature, and the time of onset and duration of action are somewhat shortened with the intravenous route of administration.

The administration of sodium pentobarbital of 30 mg/kg intravenously decreased the pyretogenic effect of 50 g/kg LSD administered intravenously in rabbits, dogs, and cats, but the rabbit was most markedly affected and hence was used for certain subsequent experiments.

Preliminary experiments were conducted in several rabbits to clarify the mechanism of the pyretogenic action of LSD. It was concluded that the pyretogenic effect of LSD is not due to a vasoconstriction of the rabbit ear preventing radiation and raising the internal temperature.

Attempts were made to lower the LSD-induced fever by administering antipyrine, dihydroergotamine, hydergine, and dibenamine, but these drugs were without effect. Sodium pentobarbital administered intravenously reduced the fever.

LSD has been reported to cause pyretogenic effects in intact animals and humans. These effects may be part of the predominant central action of LSD, or may be a side effect unconnected with its predominant central action.

References and Notes

A study was conducted on lysergic acid diethylamide by A. Hoffer, H. Osmond, and J. Smvthies, and R. Forrer and R. D. Goldner.

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