Pyridoxine is the 4-methanol form of vitamin B6 and is converted to pyridoxal 5-phosphate in the body. Vitamin B6 (pyridoxine) is a water-soluble vitamin used in the prophylaxis and treatment of vitamin B6 deficiency and peripheral neuropathy in those receiving isoniazid (isonicotinic acid hydrazide, INH). Vitamin B6 has been found to lower systolic and diastolic blood pressure in a small group of subjects with essential hypertension. Hypertension is another risk factor for atherosclerosis and coronary heart disease. Another study showed pyridoxine hydrochloride to inhibit ADP- or epinephrine-induced platelet aggregation and to lower total cholesterol levels and increase HDL-cholesterol levels, again in a small group of subjects. Vitamin B6, in the form of pyridoxal 5'-phosphate, was found to protect vascular endothelial cells in culture from injury by activated platelets. Endothelial injury and dysfunction are critical initiating events in the pathogenesis of atherosclerosis. Human studies have demonstrated that vitamin B6 deficiency affects cellular and humoral responses of the immune system. Vitamin B6 deficiency results in altered lymphocyte differentiation and maturation, reduced delayed-type hypersensitivity (DTH) responses, impaired antibody production, decreased lymphocyte proliferation and decreased interleukin (IL)-2 production, among other immunologic activities. Used for the treatment of vitamin B6 deficiency and for the prophylaxis of isoniazid-induced peripheral neuropathy.

Clofibrate is a fibric acid derivative used to lower cholesterol and triglyceride (fat-like substances) levels in the blood. This may help prevent medical problems caused by such substances clogging the blood vessels. However, this treatment was discontinued in 2002 due to adverse effects. Clofibrate is an agonist of the PPAR-α receptor in muscle, liver, and other tissues. This agonism ultimately leads to modification in gene expression resulting in increased beta-oxidation, decreased triglyceride secretion, increased HDL, and increased lipoprotein lipase activity. Clofibrate increased the activity of extrahepatic lipoprotein lipase (LL), thereby increasing lipoprotein triglyceride lipolysis, inhibited the synthesis, and increases the clearance of apolipoprotein B, a carrier molecule for VLDL. In addition, clofibrate was investigated as a novel therapy agent in multiple myeloma and it shown the promising results.

Cinnarizine is a piperazine derivative with antihistaminic, antiserotonergic, antidopaminergic, and calcium channel-blocking activities. It inhibits calcium translocation across the vestibular sensory cells in the ampullae and maintains endolymph flow by preventing constriction of the stria vascularis. It is currently used for the treatment of nausea, vomiting, and vertigo caused by Meniere’s disease and other vestibular disorders. Cinnarizine is also used for prevention and treatment of motion sickness. Chronic use of cinnarizine may induce extrapyramidal symptoms.