Side Effects

Dosing and side effects information

Most common side effects of NAMENDA

If the person you are caring for has just started or is about to start taking NAMENDA (memantine HCl), you may be wondering about the possibility of side effects.

NAMENDA may cause side effects in some patients. In clinical trials, the most common side effects occurring in at least 2% of patients treated with NAMENDA and at a greater rate than patients given placebo (sugar pill) are listed here (see chart below). Dizziness, confusion, headache, and constipation occurred at a rate of at least 5% in NAMENDA-treated patients and at a greater rate than in the placebo group.

Adverse events reported in ≥2% of patients receiving NAMENDA and
at a higher frequency than in placebo-treated patients
Most Common Side Effects NAMENDA Placebo (sugar pill)
Dizziness 7% 5%
Confusion 6% 5%
Headache 6% 3%
Constipation 5% 3%
Coughing 4% 3%
Hypertension 4% 2%
Back pain 3% 2%
Hallucination 3% 2%
Pain 3% 1%
Somnolence 3% 2%
Vomiting 3% 2%
Dyspnea 2% 1%
Fatigue 2% 1%

For a complete list of side effects associated with NAMENDA treatment, please see the full Prescribing Information.

NAMENDA® (memantine hydrochloride) is indicated for the treatment of moderate to severe dementia of the Alzheimer's type. NAMENDA is available by prescription only.

There is no evidence that NAMENDA prevents or slows the underlying disease process in patients with Alzheimer's disease.


Who should NOT take NAMENDA?
NAMENDA should not be taken by anyone who is allergic (hypersensitive) to memantine, the active substance in NAMENDA, or who has had a bad reaction to NAMENDA or any of its ingredients.

What should be discussed with the healthcare provider before taking NAMENDA?
Before starting NAMENDA, talk to the healthcare provider about all of the patient's past and present medical conditions, including:

  • Seizure disorders
  • Difficulty passing urine
  • Liver, kidney or bladder problems

If the patient is taking other medications (including those without a prescription), ask the healthcare provider if NAMENDA is right for the patient.

  • Certain medications, changes in diet, or medical conditions may affect the amount of NAMENDA in the body and possibly increase side effects.

What are the possible side effects of NAMENDA?
The most common side effects associated with NAMENDA treatment are dizziness, confusion, headache, and constipation. This is not a complete list of side effects.

Please see full Prescribing Information.

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