No significant effects of sodium aurothiomalate on haem metabolism and mixed function oxygenase activity in patients with rheumatoid arthritis

Objective. Animal studies suggest that gold compounds impair haem synthesis and increase haem degradation and, as a result, reduce activity of the hep atic haemoproteins cytochromes P-450. The aim of this study was to investig ate whether intramuscular gold exerts similar effects in patients with rheu matoid arthritis (RA). Methods. Urinary porphyrin andprecursor excretion, erythrocyte protoporphyr in, and antipyrine clearance, were measured in 6 patients with RA before an d PO weeks after commencement of intramuscular gold. Results. Parameters of haem metabolism were unaffected by gold While antipy rine clearance was;as not statistically changed after gold treatment, in 3 of the patients there was art average decrease in antipyrine clearance of 2 3%. Conclusion. Further studies examining RA patients at different time points are required to investigate further the possibility of reduced hepatic drug metabolising activity during prolonged treatment with gold.