Fluvastatin, cholesterol-lowering effects

In an isolated case, phenytoin reduced the cholesterol-lowering effect of simvastatin, fluvastatin and atorvastatin. The concurrent use of phenytoin and fluvastatin modestly raises the levels of both drugs. 

Fluvastatin, a cholesterol-lowering agent that inhibits hydroxy-methylglutaryl-coenzyme A (MHG-CoA) reductase, is effective in the reduction of low-density lipoprotein and total cholesterol levels in patients with primary hypercholesterolemia (types Ila and Ilb) when response to diet and other nonpharmacologic measures have been inadequate (see also Figure 35). 

Mitani, H., Egashira, K., and Kimura, M. (2003). HMG-CoA reductase inhibitor, fluvastatin, has cholesterol-lowering independent direct effects on atherosclerotic vessels in high cholesterol diet-fed rabbits. Pharmacol Res. 48, 417-427. 

Endocrine effects Statins interfere with cholesterol synthesis and lower circulating cholesterol levels and, as such, might theoretically blunt adrenal or gonadal steroid hormone production. Small declines in total testosterone with no commensurate elevation in LH have been noted with the use of fluvastatin. Pravastatin showed inconsistent results with regard to possible effects on basal steroid hormone levels atorvastatin, lovastatin, rosuvastatin, and simvastatin did not reduce basal plasma cortisol concentration or basal plasma testosterone concentration or impair adrenal reserve. Appropriately evaluate patients who display clinical evidence of endocrine dysfunction. Exercise caution when administering HMG-CoA reductase inhibitors with drugs that affect steroid levels or activity, such as ketoconazole, spironolactone, and cimetidine. 

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