Clofibrate, serum enzymes, and muscle pain.

Serum creatine kinas (C.K.), aspartate amino-transferase (G.O.T.), and alkaline phosphatase (A.P.) activities were measured in 211 men with serum cholesterol concentrations in the upper one-third of the normal distribution. Of these, 110 were receiving clofibrate and 101 were given identical capsules containing olive oil. These investigations were also carried out on 85 healthy men with low serum cholesterol levels not receiving clofibrate.No differences were observed in C.K. and G.O.T. activities between any of these groups; A.P. was significantly lower in the clofibrate-treated group. No significant alterations in C.K. occurred during serial observations made in 15 patients with ischaemic heart disease over a period of five months. No instance of myalgia or muscle stiffness was recorded in 452 men who had received clofibrate for one year.It is concluded that raised C.K. and G.O.T. concentrations and the occurrence of myalgia are uncommon accompaniments of clofibrate treatment.