Myopathies in systemic disease results from several different disease processes including endocrine, inflammatory, paraneoplastic, infectious, drug- and toxin-induced, critical illness myopathy, metabolic, collagen related,  and myopathies with other systemic disorders. Patients with systemic myopathies often present acutely or sub acutely. On the other hand, familial myopathies or dystrophies generally present in a chronic fashion with exceptions of metabolic myopathies where symptoms on occasion can be precipitated acutely. Most of the inflammatory myopathies can have a chance association with malignant lesions; the incidence appears to be specifically increased only in patients with dermatomyositis. 
For patients who present with rhabdomyolysis, treatment is aimed at preventing kidney failure in the acute setting. Vigorous hydration with close monitoring of kidney function and electrolytes are paramount. In patients with an underlying metabolic myopathy, education about following a more moderate exercise program and avoiding intense exercise and fasting is necessary in preventing recurrent episodes. Measures that have been suggested to be helpful include sucrose loading before exercise in some glycogen storage disorders and a low-fat, high-carbohydrate diet in patients with lipid storage disorders.
Body as a Whole: chest pain; abdominal pain; edema; chills; malaise Cardiovascular: atrial fibrillation; tachycardia; palpitations, and other cardiac arrhythmias; postural hypotension, orthostasis; hypotension; syncope Eye: toxic amblyopia; cystoid macular edema; ophthalmoplegia; eye irritation, blurred vision, progression of cataracts Gastrointestinal: activation of peptic ulcers and peptic ulceration; dyspepsia; vomiting; anorexia; constipation; flatulence, pancreatitis; hepatitis; fatty change in liver; jaundice; and rarely, cirrhosis, fulminant hepatic necrosis, and hepatoma, eructation, fatal and non-fatal hepatic failure Metabolic: gout, decreased glucose tolerance Musculoskeletal: muscle cramps; myopathy; rhabdomyolysis; arthralgia, myalgia Nervous: dizziness; insomnia; dry mouth; paresthesia; anxiety; tremor; vertigo; peripheral neuropathy; psychic disturbances; dysfunction of certain cranial nerves, nervousness, burning sensation/skin burning sensation, peripheral nerve palsy Psychiatric depression Skin: hyper-pigmentation; acanthosis nigricans; urticaria; alopecia; dry