Drug- and toxin-induced myopathies

Multiple drugs and toxins can cause myopathy. The exact incidence is unknown. Due to various subclinical forms one has to consider a high number of undetected cases. Early diagnosis is important, because these myopathies are potentially reversible on removal of the offending substance. Symptoms vary from mild muscle pain to severe muscle weakness. Rhabdomyolysis and renal failure are potentially lethal complications. The underlying mechanisms are not completely understood. This article focusses on the definition of the most common drug- and toxin-induced myopathies and gives an overview of their possible pathophysiology.