Adverse effects occurring in 2% or more of patients receiving memantine in clinical studies and more frequently than with placebo include dizziness (7%), confusion (6%), headache (6%), constipation (5%), cough (4%), hypertension (4%), back pain (3%), hallucination (3%), pain (3%), somnolence (3%), vomiting (3%), dyspnea (2%), and fatigue (2%).
Other adverse reactions: Cardiovascular:
Cardiac failure, cerebrovascular accident, syncope transient ischemic attack (at least 1%); angina pectoris, atrial fibrillation, bradycardia, cardiac arrest, hypotension, myocardial infarction, postural hypotension, pulmonary embolism, thrombophlebitis (0.1% to 1%).
Central Nervous System:
Aggressive reaction, ataxia, hypokinesia, vertigo (at least 1%); abnormal coordination, abnormal crying, abnormal thinking, amnesia, apathy, aphasia, cerebral hemorrhage, convulsions, delirium, delusion, depersonalization, emotional lability, extrapyramidal disorder, hemiplegia, hyperkinesias, hypertonia, hypesthesia, increased libido, involuntary muscle contractions, nervousness, neuralgia, neuropathy, neurosis, paranoid reaction, paresthesia, paroniria, personality disorder, psychosis, ptosis, sleep disorder, stupor, suicide attempt, tremor (0.1% to 1%).
Rash (at least 1%); alopecia, cellulitis, dermatitis, eczema, erythematous rash, pruritus, skin ulceration, urticaria (0.1% to 1%).
Diverticulitis, esophageal ulceration, gastroenteritis, GI hemorrhage, melena (0.1% to 1%).
Frequent micturition (at least 1%); dysuria, hematuria, urinary retention (0.1% to 1%).
Anemia (at least 1%); leucopenia (0.1% to 1%).
Decreased weight, increased alkaline phosphatase (at least 1%); aggravated diabetes mellitus, dehydration, hyponatremia, increased appetite (0.1% to 1%).
Pneumonia (at least 1%); apnea, asthma, hemoptysis, pulmonary edema (0.1% to 1%).
Cataract, conjunctivitis (at least 1%); abnormal lacrimation, blepharitis, blurred vision, conjunctival hemorrhage, corneal opacity, decreased hearing, decreased visual acuity, diplopia, eye pain, glaucoma, macula lutea degeneration, myopia, retinal detachment, retinal hemorrhage, tinnitus, xerophthalmia (0.1% to 1%).
Allergic reaction, hypothermia (0.1% to 1%).