Statins
Also known as: HMG-CoA reductase inhibitors
Statins are cholesterol-lowering drugs that inhibit HMG-CoA reductase, the rate-limiting enzyme of cholesterol synthesis. Drugs in the class end in "-statin," such as atorvastatin and simvastatin — lisinopril, an ACE inhibitor, is not a statin.
Statins are the first-line drug class for lowering LDL ("bad") cholesterol. They work by inhibiting HMG-CoA reductase, the rate-limiting enzyme in the liver's cholesterol synthesis pathway. With less cholesterol made internally, hepatocytes upregulate LDL receptors and pull more LDL out of the bloodstream, reducing the lipid deposits that drive atherosclerosis, heart attack, and stroke.
Members of the class share the "-statin" suffix: atorvastatin (Lipitor), simvastatin (Zocor), rosuvastatin (Crestor), pravastatin, and lovastatin. The suffix answers a common point of confusion — lisinopril is not a statin; its "-pril" suffix marks it as an ACE inhibitor used for blood pressure. Recognizing drug classes by suffix is a core pharmacy skill: -statin for lipid-lowering agents, -pril for ACE inhibitors, -olol for beta blockers.
The key adverse effects are myopathy — muscle aches that can rarely progress to rhabdomyolysis — and hepatotoxicity, which is why muscle pain and liver enzymes are monitored. Several statins, notably simvastatin and atorvastatin, are metabolized by the CYP3A4 enzyme, so inhibitors like grapefruit juice, certain antibiotics, and antifungals can raise statin levels and increase myopathy risk. Statins are also generally stopped during pregnancy — the FDA removed the blanket contraindication in 2021, but most pregnant patients are still advised to discontinue them.
Statins appear across health-science exams: the USMLE Step 1 tests the HMG-CoA reductase mechanism and adverse effects, the PTCE covers statins among cardiovascular medications and their drug interactions, and the NPTE-PT expects awareness of statin-related muscle symptoms in patients undergoing exercise testing.
Key takeaways
- Statins lower LDL cholesterol by inhibiting HMG-CoA reductase, the rate-limiting enzyme of cholesterol synthesis.
- All drugs in the class end in "-statin"; lisinopril ends in "-pril" and is an ACE inhibitor, not a statin.
- Key adverse effects are myopathy (rarely rhabdomyolysis) and elevated liver enzymes.
- CYP3A4 inhibitors such as grapefruit juice can raise levels of some statins and increase myopathy risk.
- USMLE Step 1, PTCE, and NPTE exams all test statin mechanism, interactions, or side effects.