Fluoxetine subsensitizes a nicotinic mechanism involved in the regulation of core temperature.

Fluoxetine HCl, 10 mg/kg ip, twice daily produced subsensitivity to the hypothermic effects of nicotine (base), 1 mg/kg ip, after 1 (p less than 0.02) and 2 (p less than 0.002) weeks of treatment. Phenelzine sulfate, desipramine HCl and bright artificial light produced the same effect. The capacity of three chemically distinct classes of antidepressants and bright artificial light (a treatment for seasonal depression) to produce this result suggests that effects on nicotinic mechanisms may be involved in the mechanism of action of these treatments.