For patients with cardiovascular disease, the most indispensable drugs are statins, which are also the most comfortable class of drugs used by cardiologists. Statins have good lipid-lowering efficacy and cardiovascular benefits, but the potential risks and benefits of statin use are a common concern for clinicians and patients. Therefore, statins should not only be concerned with their efficacy, but also with the possible adverse effects they may induce. After long-term attention of clinicians, it is found that statins may induce the following adverse reactions, so when using statins, you must be alert to them. One, easy to cause liver function damage, the drug is easy to affect the liver function, which is the common nature of drugs, the impact of statins on the liver is mainly manifested in the statin led to the patient’s serum alanine aminotransferase (ALT) and portal amino acid aminotransferase (AST) elevation. Second, easy to cause muscle pain, myalgia is a common adverse reaction after oral administration of statin drugs, most patients will slowly adapt or alleviate, but if persistently not relieved, you need to be alert to the possibility of rhabdomyolysis. Third, it is easy to cause blood sugar abnormalities. Long-term use of statins has an increased risk of new-onset diabetes, but its incidence has been reported inconsistently in relevant clinical experimental studies. Therefore, blood glucose abnormalities are also found after statin oral administration, and close monitoring of blood glucose is needed to guide treatment. Fourth, it is easy to cause rhabdomyolysis, which is also the most likely to occur with statins. When rhabdomyolysis occurs, there will be a series of discomfort, such as muscle pain, soreness and even renal insufficiency, fever and other symptoms, which can be identified by checking the cardiac enzyme spectrum. Fifth, cause gastrointestinal side effects, prone to loss of appetite, poor appetite, weakness, abdominal distension, etc., also more common in patients taking oral statin drugs, need to be alerted. Adverse reactions can occur with any drug, and the efficacy of statins should not be ignored because of their side effects. However, avoiding greater side effects is the way to go.