Effect of probucol on plasma lipids and lipoproteins in type IIb hyperlipoproteinemia.

Probucol was administered for 4 months in 20 adult males with Type IIb HLP in a total daily dose of 1.0 g per day. All patients had achieved a stable weight and diet response prior to entering the study. Plasma lipid and lipoprotein determinations were done at monthly intervals. Probucol produced mean reductions to TPC of -38.8 mg/dl (P < 0.0001), in LDL of -26.7 mg/dl (P < 0.001) and HDL of -8.1 mg/dl (P < 0.0001) for the entire treatment period. The mean LDL/HDL ratio increased from 5.43 to 6.08 (P < 0.02). There was no significant change in TG levels. During the study a progressive decrease in mean HDL levels from 38.9 to 29.2 mg/dl was noted. A progressive increase in the LDL/HDL ratio from 5.43 to 6.35 was also observed. These findings suggest that probucol should be used cautiously in patients with Type IIb HLP, because an inverse relationship between HDL levels and IHD incidence has been demonstrated in epidemiologic studies.