In type IIa and IIb hyperlipoproteinaemia, treatment with 16 g cholestyramine daily reduced the cholesterol concentration 23%. By adding clofibrate this effect was enhanced to a 29% reduction and at the same time clofibrate reduced the triglyceride (TG) concentration 33%. 2. The optimal cholesterol reduction with clofibrate in type II was 17% and was found after treatment with 1.5 g clofibrate/day. The optimal TG reduction appeared to be achieved with a daily dose of 2 g.3. Nicotinic acid in the form of niceritrol had another type of dose-response in type II with doses from 3 to 6 g/day. It appeared as if the optimal dose probably was above 6 g daily. The 6 g dose produced a cholesterol reduction of 22% and in type IIb there was at the same time a 50% reduction of the TG concentration. 4. By combining 3 g niceritrol with 2 g clofibrate almost the same effect on serum lipids was obtained as with 6 g niceritrol. When choosing a drug for treatment of hyperlipoproteinaemia it is necessary to consider not only the lipid lowering effect but also the side effects which are not discussed here. By combining clofibrate with either cholestyramine or niceritrol it was possible to improve the lipid lowering effect. There were no side effects which were not seen when the drugs were used alone. A more frequent use of combinations to improve the treatment of hyperlipoproteinaemia is recommended.
