Lipitor and Muscle Weakness
Muscle weakness is a common side effect of Lipitor. Based on clinical studies, this appears to be most common in people taking Lipitor 40 mg. Most people who experience muscle weakness with Lipitor have no other related symptoms; however, this can be a sign of serious problems. If you develop muscle weakness (especially if it occurs with a fever or illness), contact your healthcare provider.
While most people tolerate Lipitor® (atorvastatin calcium) well, side effects are possible. Muscle weakness is one such common side effect. In clinical studies, muscle weakness (or a general feeling of weakness) occurred in up to 3.8 percent of people taking Lipitor. Muscle weakness was most common in those taking Lipitor 40 mg and least common in people taking Lipitor 20 mg or 80 mg (0 percent).
Most people who have muscle weakness while on Lipitor have no other related symptoms. However, in less than 1 percent of cases, people develop a serious problem with their muscles while taking Lipitor, and muscle weakness can be a symptom of such a problem. Two serious muscle problems that are rarely seen in people taking this drug are myopathy and rhabdomyolysis. Rhabdomyolysis is serious because it can cause muscles to break down, which can lead to acute kidney failure, and in some cases, to loss of life.
If you develop muscle weakness, tenderness, or pain (especially if you also have a fever or feel ill) while on Lipitor, call your healthcare provider immediately. This could be a sign that you have a serious condition that needs prompt medical treatment.