Simvastatin (Zocor)

Simvastatin (Zocor) is a statin that can reduce the levels of low-density lipoprotein (LDL or ‘bad’) cholesterol in the blood. This can reduce the risk of cardiovascular disease, including heart attacks and strokes. Statins work by inhibiting the enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase, which is resposible for the production of cholesterol.

Simvastatin is available in chemists in the United Kingdom without prescription.

Patients with liver disease or who are pregnant should not take statins. However, they are safe drugs in most patients. The main side-effects are muscle pain, as well as headache, altered liver function, tingling sensations, abdominal pain, flatulence, constipation, diarrhoea, nausea and vomiting.

Simvastatin is broken down by the cytochrome P450 3A4 enzyme, and interacts with all available protease inhibitors and non-nucleoside reverse transcriptase inhibitors (NNRTIs).

Protease inhibitors cause an increase in atorvastatin levels, increasing the risk of side-effects such as muscle pain and damage to the muscle fibres.1 2 These interactions have led to the death of at least one patient.3 Consequently, patients taking protease inhibitors should use another statin such as pravastatin sodium (Lipostat) or fluvastatin (Lescol) in place of simvastatin.

In contrast, NNRTIs reduce the levels of atorvastatin, putting patients at risk of poor anti-cholesterol effects.4 Patients taking an NNRTI and atorvastatin should have their dose of atorvastatin adjusted as required to keep cholesterol levels low.

Some experts believe that statins may have anti-HIV properties in their own right. However, a recent test-tube study found no evidence of an impact of simvastatin on CD4 cell counts or viral loads.5


  1. Hsyu PH et al. Pharmacokinetic interactions between nelfinavir and 3-hydroxy-3-methylglutaryl coenzyme A inhibitors atorvastatin and simvastatin. Antimicrob Agents Chemother 45: 3445-3450, 2001
  2. Fichtenbaum CJ et al. Pharmacokinetic interactions between protease inhibitors and statins in HIV seronegative volunteers: ACTG study A5047. AIDS 16: 569-577, 2002
  3. Hare CB et al. Simvastatin-nelfinavir interaction implicated in rhabdomyolysis and death. Clin Infect Dis 35: e111-e112, 2002
  4. Gerber JG et al. Effect of efavirenz on the pharmacokinetics of simvastatin, atorvastatin and pravastatin. Results of AIDS Clinical Trials Group 5108 Study. J Acquir Immune Defic Syndr 39: 307-312, 2005
  5. Moncunill G et al. Evaluation of the anti-HIV activity of statins. AIDS 19: 1697-1700, 2005

Community Consensus Statement on Access to HIV Treatment and its Use for Prevention

Together, we can make it happen

We can end HIV soon if people have equal access to HIV drugs as treatment and as PrEP, and have free choice over whether to take them.

Launched today, the Community Consensus Statement is a basic set of principles aimed at making sure that happens.

The Community Consensus Statement is a joint initiative of AVAC, EATG, MSMGF, GNP+, HIV i-Base, the International HIV/AIDS Alliance, ITPC and NAM/aidsmap

This content was checked for accuracy at the time it was written. It may have been superseded by more recent developments. NAM recommends checking whether this is the most current information when making decisions that may affect your health.

NAM’s information is intended to support, rather than replace, consultation with a healthcare professional. Talk to your doctor or another member of your healthcare team for advice tailored to your situation.