The adverse reactions reported most frequently at the recommended dose of Amantadine Hydrochloride (5-10%) are: nausea, dizziness (lightheadedness), and insomnia.
Less frequently (1-5%) reported adverse reactions are: depression, anxiety and irritability, hallucinations, confusion, anorexia, dry mouth, constipation, ataxia, livedo reticularis, peripheral edema, orthostatic hypotension, headache, somnolence, nervousness, dream abnormality, agitation, dry nose, diarrhea and fatigue.
Infrequently (0.1-1%) occurring adverse reactions are: congestive heart failure, psychosis, urinary retention, dyspnea, fatigue, skin rash, vomiting, weakness, slurred speech, euphoria, thinking abnormality, amnesia, hyperkinesia, hypertension, decreased libido, and visual disturbance, including punctuate subepithelial or other corneal opacity, corneal edema, decreased visual acuity, sensitivity to light, and optic nerve palsy.
Rare (less than 0.1%) occurring adverse reactions are: instances of convulsion, leukopenia, neutropenia, eczematoid dermatitis, oculogyric episodes, suicidal attempt, suicide, and suicidal ideation (see WARNINGS).
Other adverse reactions reported during postmarketing experience with Amantadine Hydrochloride usage include:
coma, stupor, delirium, hypokinesia, hypertonia, delusions, aggressive behavior, paranoid reaction, manic reaction, involuntary muscle contractions, gait abnormalities, paresthesia, EEG changes, and tremor. Abrupt discontinuation may also precipitate delirium, agitation, delusions, hallucinations, paranoid reaction, stupor, anxiety, depression and slurred speech;
cardiac arrest, arrhythmias including malignant arrhythmias, hypotension, and tachycardia;
acute respiratory failure, pulmonary edema, and tachypnea;
keratitis and mydriasis;
Skin and Appendages
pruritus and diaphoresis;
neuroleptic malignant syndrome (see WARNINGS), allergic reactions including anaphylactic reactions, edema, and fever;
elevated: CPK, BUN, serum creatinine, alkaline phosphatase, LDH, bilirubin, GGT, SGOT, and SGPT.