Statins, metabolism

With the exception of pravastatin which is mainly metabolized by isomerization in the gut to a relatively inactive metabolite, the other statins undergo biotransformation by the cytochrome P-450 system. Therefore, drugs known to inhibit statin metabolism should be used cautiously. The time until maximum effect on lipids for statins is generally 4 to 6 weeks. 

Amiodarone may be another drug that necessitates special caution if used with statins metabolized by CYP3A4. 

Beyond phase I (oxidative) and phase II (conjugative) statin metabolism, variability in membrane transport also contributes strongly to myopathy risk. The organic anion transporting... 

Benameur, H., V. Jannin, D. Roulot. 2003. Method and formulation for decreasing statin metabolism, US Patent 6652865-B2. 

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