In a randomized, double-blind trial, blood levels of coenzyme Q10 (CoQ10) were measured in 45 people with high cholesterol treated with lovastatin or pravastatin (drugs related to fluvastatin) for 18 weeks.¹ A significant decline in blood levels of CoQ10 occurred with either drug. One study found that supplementation with 100 mg of CoQ10 prevented declines in CoQ10 when taken with simvastatin (another HMG-CoA reductase inhibitor drug).² Many doctors recommend that people taking HMG-CoA reductase inhibitor drugs such as fluvastatin also supplement with approximately 100 mg CoQ10 per day, although lower amounts, such as 10–30 mg per day, might conceivably be effective in preventing the decline in CoQ10 levels.

A synthetic molecule related to beta-sitosterol , sitostanol, is available in a special margarine and has been shown to lower cholesterol levels. In one study, supplementing with 1.8 grams of sitostanol per day for six weeks enhanced the cholesterol-lowering effect of various statin drugs.⁴

A supplement containing red yeast rice (Monascus purpureas) (Cholestin) has been shown to effectively lower cholesterol and triglycerides in people with moderately elevated levels of these blood lipids.⁵ This extract contains small amounts of naturally occurring HMG-CoA reductase inhibitors such as lovastatin and should not be used if you are currently taking a statin medication.

A study of 37 people with high cholesterol treated with diet and HMG-CoA reductase inhibitors found blood vitamin A levels increased during two years of therapy.⁶ Until more is known, people taking HMG-CoA reductase inhibitors, including fluvastatin, should have blood levels of vitamin A monitored if they intend to supplement vitamin A.

Niacin is the form of vitamin B3 used to lower cholesterol. Fluvastatin and niacin used together have been shown to be more effective than either substance alone.⁷ Ingestion of large amounts of niacin along with HMG-CoA reductase inhibitors such as fluvastatin may cause muscle disorders (myopathy) that can become serious (rhabdomyolysis).^{8 , 9} Such problems appear to be uncommon.^{10 , 11} Nonetheless, individuals taking fluvastatin should consult with their doctor before taking niacin.