The following adverse reactions have been reported and, within each category, are listed in order of decreasing severity.
Sedation, usually transient, may occur during the initial period of therapy or whenever the dose is increased. Headache, asthenia, or weakness may be noted as early and transient symptoms. However, significant adverse effects due to methyldopa have been infrequent and this agent usually is well tolerated.
Cardiovascular: Aggravation of angina pectoris, congestive heart failure, prolonged carotid sinus hypersensitivity, orthostatic hypotension (decrease daily dosage), edema or weight gain, bradycardia.
Digestive: Pancreatitis, colitis, vomiting, diarrhea, sialadenitis, sore or “black” tongue, nausea, constipation, distention, flatus, dryness of mouth.
Hematologic: Bone marrow depression, leukopenia, granulocytopenia, thrombocytopenia, hemolytic anemia; positive tests for antinuclear antibody, LE cells, and rheumatoid factor, positive Coombs test.
Hepatic: Liver disorders including hepatitis, jaundice, abnormal liver function tests (see WARNINGS).Hypersensitivity: Myocarditis, pericarditis, vasculitis, lupus-like syndrome, drug-related fever, eosinophilia.
Nervous System/Psychiatric: Parkinsonism, Bell's palsy, decreased mental acuity, involuntary choreoathetotic movements, symptoms of cerebrovascular insufficiency, psychic disturbances including nightmares and reversible mild psychoses or depression, headache, sedation, asthenia or weakness, dizziness, lightheadedness, paresthesias.
Metabolic: Rise in BUN.
Musculoskeletal: Arthralgia, with or without joint swelling; myalgia.
Respiratory: Nasal stuffiness.
Skin: Toxic epidermal necrolysis, rash.
Urogenital: Amenorrhea, breast enlargement, gynecomastia, lactation, impotence, decreased libido.
Body as a Whole: Weakness.
Cardiovascular: Hypotension including orthostatic hypotension (may be aggravated by alcohol, barbiturates, narcotics or antihypertensive drugs).
Digestive: Pancreatitis, jaundice (intrahepatic cholestatic jaundice), diarrhea, vomiting, sialadenitis, cramping, constipation, gastric irritation, nausea, anorexia.
Hematologic: Aplastic anemia, agranulocytosis, leukopenia, hemolytic anemia, thrombocytopenia.
Hypersensitivity: Anaphylactic reactions, necrotizing angiitis (vasculitis and cutaneous vasculitis), respiratory distress including pneumonitis and pulmonary edema, photosensitivity, fever, urticaria, rash, purpura.
Metabolic:Electrolyte imbalance (see PRECAUTIONS), hyperglycemia, glycosuria, hyperuricemia.
Nervous System/Psychiatric: Vertigo, paresthesias, dizziness, headache, restlessness.
Renal: Renal failure, renal dysfunction, interstitial nephritis. (See WARNINGS.)
Skin: Erythema multiforme including Stevens-Johnson syndrome, exfoliative dermatitis including toxic epidermal necrolysis, alopecia.
Special Senses: Transient blurred vision, xanthopsia.