Abstract

The term ‘acetylator polymorphism’ describes genetically determined differences in ability to metabolise certain drugs by acetylation (see table). About 60% of people in Britain acetylate these drugs slowly (slow acetylator phenotype), while the remainder are rapid acetylators. Rapid acetylation is much more common among the Japanese, Chinese and Eskimos. Phenotypes may be identified by giving the patient a single dose of sulphadimidine and measuring the proportions of free and acetylated drug that appear in the plasma and urine.^1–3 But whether widespread acetylator phenotyping of patients will significantly improve their management is not yet clear.