Namenda Side Effects

Please note - some side effects for Namenda may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA at http://www.fda.gov/medwatch/ or 1-800-FDA-1088 (1-800-332-1088).

Side Effects of Namenda - for the Consumer

Namenda

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome when using Namenda:

Constipation; dizziness; headache; pain.

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); change in behavior, such as aggressiveness, depression, or anxiety; chest pain or tightness; fainting; hallucinations; one-sided weakness; severe tiredness; speech changes; sudden severe headache; vision changes.

Namenda Solution

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome when using Namenda Solution:

Constipation; dizziness; headache; pain.

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); change in behavior, such as aggressiveness, depression, or anxiety; chest pain or tightness; fainting; hallucinations; one-sided weakness; severe tiredness; speech changes; sudden severe headache; vision changes.

Namenda Tablets

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome when using Namenda Tablets:

Constipation; dizziness; headache; pain.

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); change in behavior, such as aggressiveness, depression, or anxiety; chest pain or tightness; fainting; hallucinations; one-sided weakness; severe tiredness; speech changes; sudden severe headache; vision changes.

Namenda Side Effects - for the Professional

Namenda

The experience described in this section derives from studies in patients with Alzheimer's disease and vascular dementia.

Adverse Events Leading to Discontinuation: In placebo-controlled trials in which dementia patients received doses of Namenda up to 20 mg/day, the likelihood of discontinuation because of an adverse event was the same in the Namenda group as in the placebo group. No individual adverse event was associated with the discontinuation of treatment in 1% or more of Namenda-treated patients and at a rate greater than placebo.

Adverse Events Reported in Controlled Trials: The reported adverse events in Namenda (memantine hydrochloride) trials reflect experience gained under closely monitored conditions in a highly selected patient population. In actual practice or in other clinical trials, these frequency estimates may not apply, as the conditions of use, reporting behavior and the types of patients treated may differ. Table 1 lists treatment-emergent signs and symptoms that were reported in at least 2% of patients in placebo-controlled dementia trials and for which the rate of occurrence was greater for patients treated with Namenda than for those treated with placebo. No adverse event occurred at a frequency of at least 5% and twice the placebo rate.

Other adverse events occurring with an incidence of at least 2% in Namenda-treated patients but at a greater or equal rate on placebo were agitation, fall, inflicted injury, urinary incontinence, diarrhea, bronchitis, insomnia, urinary tract infection, influenza-like symptoms, abnormal gait, depression, upper respiratory tract infection, anxiety, peripheral edema, nausea, anorexia, and arthralgia.

The overall profile of adverse events and the incidence rates for individual adverse events in the subpopulation of patients with moderate to severe Alzheimer's disease were not different from the profile and incidence rates described above for the overall dementia population.

Vital Sign Changes: Namenda and placebo groups were compared with respect to (1) mean change from baseline in vital signs (pulse, systolic blood pressure, diastolic blood pressure, and weight) and (2) the incidence of patients meeting criteria for potentially clinically significant changes from baseline in these variables. There were no clinically important changes in vital signs in patients treated with Namenda. A comparison of supine and standing vital sign measures for Namenda and placebo in elderly normal subjects indicated that Namenda treatment is not associated with orthostatic changes.

Laboratory Changes: Namenda and placebo groups were compared with respect to (1) mean change from baseline in various serum chemistry, hematology, and urinalysis variables and (2) the incidence of patients meeting criteria for potentially clinically significant changes from baseline in these variables. These analyses revealed no clinically important changes in laboratory test parameters associated with Namenda treatment.

ECG Changes: Namenda and placebo groups were compared with respect to (1) mean change from baseline in various ECG parameters and (2) the incidence of patients meeting criteria for potentially clinically significant changes from baseline in these variables. These analyses revealed no clinically important changes in ECG parameters associated with Namenda treatment.

Other Adverse Events Observed During Clinical Trials

Namenda has been administered to approximately 1350 patients with dementia, of whom more than 1200 received the maximum recommended dose of 20 mg/day. Patients received Namenda treatment for periods of up to 884 days, with 862 patients receiving at least 24 weeks of treatment and 387 patients receiving 48 weeks or more of treatment.

Treatment emergent signs and symptoms that occurred during 8 controlled clinical trials and 4 open-label trials were recorded as adverse events by the clinical investigators using terminology of their own choosing. To provide an overall estimate of the proportion of individuals having similar types of events, the events were grouped into a smaller number of standardized categories using WHO terminology, and event frequencies were calculated across all studies.

All adverse events occurring in at least two patients are included, except for those already listed in Table 1, WHO terms too general to be informative, minor symptoms or events unlikely to be drug-caused, e.g., because they are common in the study population. Events are classified by body system and listed using the following definitions: frequent adverse events - those occurring in at least 1/100 patients; infrequent adverse events - those occurring in 1/100 to 1/1000 patients. These adverse events are not necessarily related to Namenda treatment and in most cases were observed at a similar frequency in placebo-treated patients in the controlled studies.

Body as a Whole:Frequent: syncope. Infrequent: hypothermia, allergic reaction.

Cardiovascular System:Frequent: cardiac failure. Infrequent: angina pectoris, bradycardia, myocardial infarction, thrombophlebitis, atrial fibrillation, hypotension, cardiac arrest, postural hypotension, pulmonary embolism, pulmonary edema.

Central and Peripheral Nervous System:Frequent: transient ischemic attack, cerebrovascular accident, vertigo, ataxia, hypokinesia. Infrequent: paresthesia, convulsions, extrapyramidal disorder, hypertonia, tremor, aphasia, hypoesthesia, abnormal coordination, hemiplegia, hyperkinesia, involuntary muscle contractions, stupor, cerebral hemorrhage, neuralgia, ptosis, neuropathy.

Gastrointestinal System:Infrequent: gastroenteritis, diverticulitis, gastrointestinal hemorrhage, melena, esophageal ulceration.

Hemic and Lymphatic Disorders:Frequent: anemia. Infrequent: leukopenia.

Metabolic and Nutritional Disorders:Frequent: increased alkaline phosphatase, decreased weight. Infrequent: dehydration, hyponatremia, aggravated diabetes mellitus.

Psychiatric Disorders:Frequent: aggressive reaction. Infrequent: delusion, personality disorder, emotional lability, nervousness, sleep disorder, libido increased, psychosis, amnesia, apathy, paranoid reaction, thinking abnormal, crying abnormal, appetite increased, paroniria, delirium, depersonalization, neurosis, suicide attempt.

Respiratory System:Frequent: pneumonia. Infrequent: apnea, asthma, hemoptysis.

Skin and Appendages:Frequent: rash. Infrequent: skin ulceration, pruritus, cellulitis, eczema, dermatitis, erythematous rash, alopecia, urticaria.

Special Senses:Frequent: cataract, conjunctivitis. Infrequent: macula lutea degeneration, decreased visual acuity, decreased hearing, tinnitus, blepharitis, blurred vision, corneal opacity, glaucoma, conjunctival hemorrhage, eye pain, retinal hemorrhage, xerophthalmia, diplopia, abnormal lacrimation, myopia, retinal detachment.

Urinary System:Frequent: frequent micturition. Infrequent: dysuria, hematuria, urinary retention.

Events Reported Subsequent to the Marketing of Namenda, both US and Ex-US

Although no causal relationship to memantine treatment has been found, the following adverse events have been reported to be temporally associated with memantine treatment and are not described elsewhere in labeling: aspiration pneumonia, asthenia, atrioventricular block, bone fracture, carpal tunnel syndrome, cerebral infarction, chest pain, cholelithiasis, claudication, colitis, deep venous thrombosis, depressed level of consciousness (including loss of consciousness and rare reports of coma), dyskinesia, dysphagia, encephalopathy, gastritis, gastroesophageal reflux, grand mal convulsions, intracranial hemorrhage, hepatitis (including increased ALT and AST and hepatic failure), hyperglycemia, hyperlipidemia, hypoglycemia, ileus, increased INR, impotence, lethargy, malaise, myoclonus, neuroleptic malignant syndrome, acute pancreatitis, Parkinsonism, acute renal failure (including increased creatinine and renal insufficiency), prolonged QT interval, restlessness, sepsis, Stevens-Johnson syndrome, suicidal ideation, sudden death, supraventricular tachycardia, tachycardia, tardive dyskinesia, thrombocytopenia, and hallucinations (both visual and auditory).

Side Effects by Body System

Cardiovascular

Cardiovascular side effects have included hypertension (4%). Cardiac failure, angina pectoris, bradycardia, myocardial infarction, thrombophlebitis, atrial fibrillation, hypotension, cardiac arrest, postural hypotension, pulmonary embolism, and pulmonary edema have been reported during clinical trials, but no direct correlation to memantine has been established. Atrioventricular block, prolonged QT interval, supraventricular tachycardia, and tachycardia have been reported subsequent to the worldwide marketing of memantine.

Nervous system

In a trial testing the use of memantine in MS patients with cognitive impairment, nine out of nineteen patients reported a worsening of their neurologic symptoms that deteriorated their quality of life. After stopping the medication, the patients reverted to their baseline disability within a few days.

Nervous system side effects have included dizziness (7%) and headache (6%). Transient ischemic attack, cerebrovascular accident, vertigo, ataxia, hypokinesia, paresthesia, convulsions, extrapyramidal disorder, hypertonia, tremor, aphasia, hypoesthesia, abnormal coordination, hemiplegia, hyperkinesia, involuntary muscle contractions, stupor, cerebral hemorrhage, neuralgia, ptosis, and neuropathy have been reported during clinical trials, but these adverse events may not be necessarily related to memantine. Carpal tunnel syndrome, cerebral infarction, grand mal convulsions, intracranial hemorrhage, and neuroleptic malignant syndrome have been reported subsequent to the worldwide marketing of memantine.

Gastrointestinal

Gastrointestinal side effects have included constipation (5%) and vomiting (3%). Gastroenteritis, diverticulitis, gastrointestinal hemorrhage, melena, and esophageal ulceration have been reported during clinical trials, but no direct correlation to memantine has been established. Colitis, dysphagia, gastritis, ileus, acute pancreatitis, gastroesophageal reflux have been reported subsequent to the worldwide marketing of memantine.

Musculoskeletal

Musculoskeletal side effects have included back pain (3%), bone fracture, tardive dyskinesia, and dyskinesia.

Psychiatric

Psychiatric side effects have included confusion (6%), somnolence (3%), and hallucination (3%). Aggressive reaction, delusion, personality disorder, emotional lability, nervousness, sleep disorder, libido increased, psychosis, amnesia, apathy, paranoid reaction, thinking abnormal, crying abnormal, appetite increased, paroniria, delirium, depersonalization, neurosis, and suicide attempt have been reported during clinical trials although not direct correlation to memantine has been established,

Respiratory

Respiratory side effects have included coughing (4%) and dyspnea (2%). Pneumonia, apnea, asthma, and hemoptysis have been reported during clinical trials although these adverse events may not be necessarily related to memantine.

Hematologic

Hematologic side effects reported during clinical trials have included anemia and leukopenia, although no direct relationship to memantine has been established. Postmarketing adverse events reporting from outside the U.S. have included thrombocytopenia. Thrombocytopenia and hyperlipidemia have been reported subsequent to the worldwide marketing of memantine.

Dermatologic

Dermatologic side effects reported during clinical trials have included rash, skin ulceration, pruritus, cellulitis, eczema, dermatitis, erythematous rash, alopecia and urticaria although these adverse events may not be necessarily related to memantine.
Stevens-Johnson syndrome has been reported subsequent to the worldwide marketing of memantine. Postmarketing adverse events reporting from outside the U.S. have included acne.

Metabolic

Metabolic side effects reported during clinical trials have included increased alkaline phosphatase, decreased weight, dehydration, hyponatremia, and aggravated diabetes mellitus although these adverse events may not be necessarily related to memantine.

Ocular

Ocular side effects reported during clinical trials have included cataract, conjunctivitis, macula lutea degeneration, decreased visual acuity, decreased hearing, tinnitus, blepharitis, blurred vision, corneal opacity, glaucoma, conjunctival hemorrhage, eye pain, retinal hemorrhage, xerophthalmia, diplopia, abnormal lacrimation, myopia, and retinal detachment although these adverse events may not be necessarily related to memantine.

Genitourinary

Genitourinary side effects reported during clinical trials have included frequent micturition, dysuria, hematuria, and urinary retention, although these adverse events may not be necessarily related to memantine treatment. Postmarketing adverse events reporting outside the U.S. have included impotence.

Other

Other side effects including claudication, chest pain, malaise, restlessness, and sudden death have been reported subsequent to the worldwide marketing of memantine.

Hepatic

Hepatic side effects have included hepatic failure, which was reported subsequent to the worldwide marketing of memantine.

Renal

Renal side effects have included acute renal failure, which has been reported subsequent to the worldwide marketing of memantine.

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