ABSTRACT
In order to facilitate prompt diagnosis and, where possible, avoidance, this chapter provides an overview of common perpetrators of drug-related muscle pain. Skeletal muscle makes up a large portion of the body's mass and receives a large amount of blood supply. Due to its metabolic activity, many drugs that enter the body's circulatory system are passed throughout skeletal muscles leading to various drug-induced disorders. Adverse drug effects on muscle include myalgias, myositis, and rhabdomyolysis. Myalgia is muscle pain that is characterized by diffuse muscle pain, tenderness, and cramps. This can be associated with muscle weakness, but it is not always a characteristic. Myositis is inflammation of voluntary muscle fibers and is associated with muscle symptoms that are similar to myalgia in addition to elevations in serum creatine kinase. Corticosteroid-induced myalgia is a result of the chronic use of oral corticosteroids that can cause proximal muscle weakness and atrophy of lower limbs. It does not result from acute use of corticosteroids.
