Simvastatin should be taken as prescribed by your doctor as many times a day as you can, usually taking it once a day. Since the strength of simvastatin in lowering LDL is relatively weak, it is recommended that it be taken daily before bedtime for relatively reliable efficacy. Simvastatin is a statin lipid-regulating drug that inhibits cholesterol synthesis and primarily lowers LDL cholesterol. The duration of action of simvastatin is relatively long, usually taken once a day, and because the enzymes of cholesterol synthesis are better inhibited by taking statin at night, it is recommended to take it before going to bed for more reliable efficacy. If the lipid control is stable and relatively safe after taking simvastatin, the doctor will advise the patient to take it for a long time. Only long-term use can keep lipid control at a stable level, prevent atherosclerosis, and prevent cardiovascular disease. Sometimes it depends on the dosage form of different manufacturers. Generally, 20 mg/day is needed, and 40 mg/day may be needed for some of the LDL not to meet the standard.