Which adverse effect is important to monitor with statin therapy such as atorvastatin or simvastatin?

• A. Rhabdomyolysis
• B. Hypertension
• C. Tinnitus
• D. Constipation

Answer: (A)

The main concept is that statins can cause muscle injury, and the most important adverse effect to monitor is rhabdomyolysis. Rhabdomyolysis is a severe breakdown of skeletal muscle that releases myoglobin and other contents into the blood, which can overwhelm the kidneys and cause acute kidney injury. Because of this risk, be vigilant for signs like unexplained muscle pain, tenderness, weakness, or dark urine. If these occur, evaluate with creatine kinase and kidney function tests, and typically hold the statin until assessment. Hydration and supportive care are key, and depending on the situation, dose adjustment or switching to another statin may be considered. The risk is higher with high doses and with drug interactions (such as certain antibiotics or antifungals, fibrates, niacin, cyclosporine) or with grapefruit juice, older age, or renal impairment. Other listed effects—hypertension, tinnitus, constipation—are not the classic concerns with statins.