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Originally Posted by AMlabs
Statins?
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A little bit of info for ya on Satins AM.
Statins are a class of drugs used to treat high lipids, especially high LDL cholesterol. They include simvastatin (Zocor), pravastatin (Lipostat), fluvastatin (Lescol / Lescol XL), atorvastatin (Lipitor), cerivastatin and rosuvastatin (Crestor). The statins are more effective than other classes of lipid-lowering drugs at reducing LDL cholesterol, but less effective than the fibrates in reducing triglycerides and increasing HDL cholesterol. In the general population, they reduce the risk of heart disease, stroke, diabetes and death.
Statins are generally regarded as very safe drugs, although their main side-effects are gastrointestinal problems (nausea, vomiting, flatulence and stomach pain) and inflammation of the muscles. A person taking a statin is advised to report muscle weakness, tenderness or pain to their doctor promptly. The risk of muscle pain and weakness is increased if a statin is taken with gemfibrozil (Lopid), ciclosporin (Neoral / Sandimmun) or nicotinic acid. Kidney and liver function should be closely monitored if these drugs are taken with a statin.
Most statins are metabolised in the liver in a similar way to the protease inhibitors, primarily using the P450 CYP3A4 pathway. Some protease inhibitors cause substantial and potentially dangerous increases in blood levels of statins, increasing the risk of muscle damage. Drug interaction studies in HIV-negative subjects found large increases in atorvastatin and simvastatin levels when dosed with saquinavir (Invirase / Fortovase) and ritonavir (Norvir). However, the decline in pravastatin levels was less pronounced, indicating this may be the safest statin for use with protease inhibitors. Another study has recommended that simvastatin not be taken with nelfinavir (Viracept) due to a drug interaction, and that caution should be exercised when nelfinavir and atorvastatin are co-administered. Similarly, efavirenz (Sustiva) can cause reduced exposure to simvastatin, pravastatin and atorvastatin, possibly requiring higher doses to maintin the drugs' lipid-lowering actions (Gerber 2005).
In contrast to other members of the drug class, rosuvastatin is not metabolised by the P450 pathway. A pilot study has shown that it is a safe and effective treatment for increased cholesterol and triglycerides in patients taking protease inhibitors (Calza 2005).
Other drugs can also interact with the statins. For example, when fluvastatin is taken concurrently with fluconazole (Diflucan), levels of fluvastatin are elevated and exposure is prolonged.
A recent study has suggested that statins may also have a direct antiretroviral activity, through their inhibition of the enzyme Rho guanosine triphosphatase. This prevents the formation of the protein Rho, which is necessary for the entry of HIV into T-cells and the release of virus particles from infected cells. In their small proof-of-concept study, the investigators showed that giving lovastatin to antiretroviral-naive patients for one month caused reductions in viral load and increases in CD4 cell counts (del Real 2004). However, this finding requires verification in further clinical studies.
Similarly, some doctors have expressed concern that statins may affect the levels of immune system cells and chemical messengers or 'cytokines', potentially altering the course of HIV disease or therapy. Despite their beneficial effects on lipid levels, they warn that more research is needed to establish whether the drugs have long-term effects on the immune system (Corrales-Medina 2005).