Abstract
The effect of long-term treatment with flupenthixol on hepatic microsomal enzyme activity was studied in 12 chronic schizophrenic outpatients who had been receiving two weekly maintenance doses for at least 6 months. Antipyrine half-life was measured in the 12 patients while they continued to receive the drug. Flupenthixol was then discontinued for 6 weeks and antipyrine half-life was repeated in 7 of the 12 patients. In the 12 patients the plasma antipyrine elimination half-life was 4–24 h (mean 9.73±1.61 h) when receiving flupenthixol and there was a significant negative correlation between antipyrine half-life and the dose of flupenthixol (r=0.582, P<0.05). In the seven patients to whom antipyrine was given on two occasions, antipyrine half-life was 7.33±1.07 h and 12.04±1.87 h on and off flupenthixol treatment respectively. The clearance significantly decreased when flupenthixol was discontinued, but there was no change in the apparent volume of distribution.
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Salem, S.A.M., King, D.J. & McDevitt, D.G. Induction of microsomal enzyme activity by flupenthixol in chronic schizophrenics. Psychopharmacology 78, 147–149 (1982). https://doi.org/10.1007/BF00432253
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DOI: https://doi.org/10.1007/BF00432253