Medical Editor: John P. Cunha, DO, FACOEP
Namzaric (memantine hydrochloride extended-release and donepezil hydrochloride) is a combination of an orally active NMDA receptor antagonist, and a reversible inhibitor of the enzyme acetylcholinesterase, used to treat moderate to severe dementia of the Alzheimer's type in patients stabilized on memantine hydrochloride and donepezil hydrochloride. Common side effects of Namzaric include:
- flu symptoms
- high or low blood pressure
- abdominal pain
- weight gain
- back pain
- aggression, and
- urinary incontinence
Patients stabilized on memantine hydrochloride and donepezil hydrochloride can be switched to Namzaric 28 mg/10 mg, taken once a day in the evening. Namzaric may interact with NMDA antagonists, anticholinergics, succinylcholine, similar neuromuscular blocking agents, or cholinergic agonists. Tell your doctor all medications and supplements you use. During pregnancy, Namzaric should only be taken if prescribed. It is unknown if this drug passes into breast milk. Consult your doctor before breastfeeding.
Our Namzaric (memantine hydrochloride extended-release and donepezil hydrochloride) Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
The following serious adverse reactions are discussed below and elsewhere in the labeling.
- Cardiovascular Conditions [see WARNINGS AND PRECAUTIONS]
- Peptic Ulcer Disease and Gastrointestinal Bleeding [see WARNINGS AND PRECAUTIONS]
- Nausea and Vomiting [see WARNINGS AND PRECAUTIONS]
- Genitourinary Conditions [see WARNINGS AND PRECAUTIONS]
- Seizures [see WARNINGS AND PRECAUTIONS]
- Pulmonary Conditions [see WARNINGS AND PRECAUTIONS]
Clinical Trials Experience
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
Memantine hydrochloride extended-release was evaluated in a double-blind, placebo-controlled trial in 676 patients with moderate to severe dementia of the Alzheimer's type (341 patients treated with memantine 28 mg/day dose and 335 patients treated with placebo) for a treatment period up to 24 weeks. Of the patients randomized, 236 treated with memantine 28 mg/day and 227 treated with placebo were on a stable dose of donepezil for 3 months prior to screening.
Adverse Reactions Leading To Discontinuation With Memantine Hydrochloride
In the placebo-controlled clinical trial of memantine hydrochloride extended-release, the proportion of patients in the memantine hydrochloride extended-release 28 mg/day dose group and in the placebo group who discontinued treatment due to adverse reactions was 10% and 6%, respectively. The most common adverse reaction in the memantine hydrochloride extended-release treated group that led to treatment discontinuation was dizziness, at a rate of 1.5%.
Most Common Adverse Reactions With Memantine Hydrochloride
The most common adverse reactions with memantine hydrochloride extended-release in patients with moderate to severe Alzheimer's disease, defined as those occurring at a frequency of at least 5% in the memantine hydrochloride extended-release group and at a higher frequency than placebo, were headache, diarrhea, and dizziness.
Table 1 lists adverse reactions that occurred at an incidence of ≥ 2% in the memantine hydrochloride extended-release treated group and occurred at a rate greater than placebo.
Table 1: Adverse reactions with memantine
hydrochloride extended-release in patients with moderate to severe Alzheimer's
(n = 335) %
|Memantine hydrochloride extended-release 28 mg
(n = 341) %
|Infections and Infestations|
|Musculoskeletal and Connective Tissue Disorders|
|Nervous System Disorders|
|Renal and Urinary Disorders|
Adverse Reactions Leading to Discontinuation with Donepezil Hydrochloride
In controlled clinical trials of donepezil hydrochloride, the rate of discontinuation due to adverse reactions for patients treated with donepezil hydrochloride was approximately 12%, compared to 7% for patients treated with placebo. The most common adverse reactions leading to discontinuation, defined as those occurring in at least 2% of donepezil hydrochloride patients and at twice or more the incidence seen with placebo, were anorexia (2%), nausea (2%), diarrhea (2%) and urinary tract infection (2%).
Most Common Adverse Reactions with Donepezil Hydrochloride
The most common adverse reactions reported with donepezil hydrochloride in controlled clinical trials in patients with severe Alzheimer's disease, defined as those occurring at a frequency of at least 5% in the donepezil hydrochloride group and at twice or more the placebo rate, were diarrhea, anorexia, vomiting, nausea, and ecchymosis. The most common adverse reactions reported with donepezil hydrochloride in controlled clinical trials in patients with mild to moderate Alzheimer's disease were insomnia, muscle cramp, and fatigue.
Table 2 lists adverse reactions that occurred at an incidence of ≥ 2% in the donepezil hydrochloride group and at a rate greater than placebo in controlled trials in patients with severe Alzheimer's disease.
Table 2: Adverse reactions with donepezil
hydrochloride in patients with severe Alzheimer's disease
|Body System/Adverse Event||Placebo
(n = 392) %
|Donepezil hydrochloride 10 mg/day
(n = 501) %
|Percent of Patients with any Adverse Event||73||81|
|Body as a Whole|
|Chest pain||< 1||2|
|Hemic and Lymphatic System|
|Metabolic and Nutritional Systems|
|Increased creatine phosphokinase||1||3|
|Skin and Appendages|
The following adverse reactions have been identified during post-approval use of memantine hydrochloride and donepezil hydrochloride. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
Acute renal failure, agranulocytosis, cardiac failure congestive, hepatitis, leukopenia (including neutropenia), pancreatitis, pancytopenia, Stevens-Johnson syndrome, suicidal ideation, thrombocytopenia, and thrombotic thrombocytopenic purpura.
Abdominal pain, agitation, cholecystitis, confusion, convulsions, hallucinations, heart block (all types), hemolytic anemia, hepatitis, hyponatremia, neuroleptic malignant syndrome, pancreatitis, and rash.
Read the entire FDA prescribing information for Namzaric (Memantine Hydrochloride Extended-release and Donepezil Hydrochloride Capsules)