It can often be treated by drugs like corticosteroids or immunosuppressants. Inclusion body myositis is a slowly progressive disease that produces weakness of hand grip and straightening of the knees. No effective treatment is known. (M61) Myositis ossificans
(M62.89) Rhabdomyolysis and (R82.1) myoglobinuriasThe Food and Drug Administration is recommending that physicians restrict prescribing high-dose Simvastatin (Zocor, Merck) to patients, given an increased risk of muscle damage. The FDA drug safety communication stated that physicians should limit using the 80-mg dose unless the patient has already been taking the drug for 12 months and there is no evidence of myopathy. "Simvastatin 80 mg should not be started in new patients, including patients already taking lower doses of the drug," the agency states. Statin-associated autoimmune myopathy

Myocardium / cardio-myopathy
(I40) Acute myocarditis
(I41) Myocarditis in diseases classified elsewhere
(I42) Cardiomyopathy
(I42.0) Dilated cardiomyopathy
(I42.1) Obstructive hypertrophy cardiomyopathy
(I42.2) Other hypertrophic cardiomyopathy
(I42.3) Endomyocardial (eosinophilic) disease
Eosinophilic myocarditis
Endomyocardial (tropical) fibrosis
Löfflers endocarditis
(I42.4) Endocardial fibroelastosis
(I42.5) Other restrictive cardiomyopathy
(I42.6) Alcoholic cardiomyopathy
(I42.8) Other cardiomyopathies
Arrhythmogenic right ventricular dysplasia
(I43) Cardiomyopathy in diseases classified elsewhere

Differential diagnosis
At birth

None as systemic causes; mainly hereditaryOnset in childhood

Inflammatory myopathies – dermatomyositis, polymyositis (rarely)
Infectious myopathies
Endocrine and metabolic disorders – hypokalemia, hypocalcemia, hypercalcemiaOnset in adulthood
Inflammatory myopathies – polymyositis, dermatomyositis, inclusion body myositis, viral (HIV)
Infectious myopathies
Endocrine myopathies – thyroid, parathyroid, adrenal, pituitary disorders
Toxic myopathies – alcohol, corticosteroids, narcotics, colchicines, chloroquine
Critical illness myopathy
Metabolic myopathies
Paraneoplastic myopathy

Treatments
Because different types of myopathies are caused by many different pathways, there is no single treatment for myopathy. Treatments range from treatment of the symptoms to very specific cause-targeting treatments.
Inherited forms
(G71.0) Dystrophies (or muscular dystrophies) are a subgroup of myopathies characterized by muscle degeneration and regeneration. Clinically, muscular dystrophies are typically progressive, because the muscles ability to regenerate is eventually lost, leading to progressive weakness, often leading to use of a wheelchair, and eventually death, usually related to respiratory weakness. (G71.1) Myotonia
Neuromyotonia
(G71.2) The congenital myopathies do not show evidence for either a progressive dystrophic process (i.e., muscle death) or inflammation, but instead characteristic microscopic changes are seen in association with reduced contractile ability of the muscles.