section name header

Table 195-2

Drug-Induced Myopathies

DrugsMajor Toxic Reaction

Lipid-lowering agents

Fibric acid derivatives

HMG-CoA reductase inhibitors

Niacin (nicotinic acid)

Drugs belonging to all three of the major classes of lipid-lowering agents can produce a spectrum of toxicity: asymptomatic serum creatine kinase elevation, myalgias, exercise-induced pain, rhabdomyolysis, and myoglobinuria.
GlucocorticoidsAcute, high-dose glucocorticoid treatment can cause acute quadriplegic myopathy. These high doses of steroids are often combined with nondepolarizing neuromuscular blocking agents but the weakness can occur without their use. Chronic steroid administration produces predominantly proximal weakness.
Nondepolarizing neuromuscular blocking agentsAcute quadriplegic myopathy can occur with or without concomitant glucocorticoids.
ZidovudineMitochondrial myopathy with ragged red fibers

Drugs of abuse

Alcohol

Amphetamines

Cocaine

Heroin

Phencyclidine

Meperidine

All drugs in this group can lead to widespread muscle breakdown, rhabdomyolysis, and myoglobinuria.

Local injections cause muscle necrosis, skin induration, and limb contractures.

Autoimmune toxic myopathy

D-Penicillamine

Use of this drug may cause polymyositis and myasthenia gravis.

Amphophilic cationic drugs

Amiodarone

Chloroquine

Hydroxychloroquine

All amphophilic drugs have the potential to produce painless, proximal weakness associated with autophagic vacuoles in the muscle biopsy.

Antimicrotubular drugs

Colchicine

This drug produces painless, proximal weakness especially in the setting of renal failure. Muscle biopsy shows autophagic vacuoles.