A case of risperidone-induced hypothermia

Area of Science:

• Pharmacology and Neuroscience
• Clinical Medicine

Background:

• Second-generation antipsychotics (SGAs), like risperidone, are increasingly used due to improved efficacy and safety over typical antipsychotics.
• SGAs modulate dopamine D(2) and serotonin 5-HT(2) receptors, influencing both positive and negative symptoms of schizophrenia.
• Risperidone exhibits a higher affinity for 5-HT(2) receptors than D(2) receptors, contributing to its therapeutic profile and side effect spectrum.

Observation:

• Common risperidone side effects include extrapyramidal symptoms, dizziness, nausea, weight gain, sleep disturbances, and sexual dysfunction.
• This report details a rare case of risperidone-induced hypothermia, an adverse event not typically highlighted.
• Body temperature regulation involves complex neurochemical pathways, including dopaminergic, serotonergic, and adrenergic systems in the hypothalamus.

Findings:

• Experimental data suggest that stimulation of 5-HT(2) and dopamine receptors can elevate body temperature.
• Conversely, potent antagonists of 5-HT(2) receptors are associated with an increased risk of hypothermia.
• Given risperidone's higher potency in blocking 5-HT(2) receptors compared to D(2) receptors, it may predispose individuals to hypothermia.

Implications:

• The findings suggest a potential mechanism for risperidone-induced hypothermia, related to its specific receptor binding profile.
• Clinicians should be aware of this rare but significant side effect, particularly in vulnerable patient populations.
• Further research into the thermoregulatory effects of SGAs and their receptor interactions is warranted to optimize patient safety.