Abstract
Eleven Ghanaian and 12 Swedish subjects phenotyped with a debrisoquine (D) hydroxylation test were given a single oral dose of nortriptyline (NT). Much the same percentage of the given NT dose was excreted as 10‐hydroxy‐NT (10‐OH‐NT) by Ghanaians (43.1%) and Swedes (49.2%). There was a close correlation between plasma clearance of NT by 10‐hydroxylation and the D metabolic ratio (D/4‐OH‐D in urine) in the Ghanaians (rs = −0.95; P < 0.01) and Swedes (rs = −0.84; P < 0.01). The E‐isomer of 10‐OH‐NT is the major isomer in both Ghanaians (76% to 92% of total 10‐OH‐NT) and Swedes (78% to 95%). It is suggested that the E‐10‐hydroxylation of NT and the 4‐hydroxylation of D are similarly coregulated in Ghanaians and Swedes.
Clinical Pharmacology and Therapeutics (1984) 36, 374–378; doi:10.1038/clpt.1984.190