NAMENDA XR® Safety Profile

NAMENDA XR side effects and pharmacokinetic drug interactions

Adverse reactions observed with a frequency of ≥2% and occurring at a rate greater than placebo1


Adverse reaction
NAMENDA XR 28mg+AChEI
(n=341)
%
Placebo+AChEI
(n=335)
%
Gastrointestinal disorders
Diarrhea
5
4
Constipation
3
1
Abdominal Pain
2
1
Vomiting
2
1
Infections and infestations
Influenza
4
3
Investigations
Weight, increased
3
1
Musculoskeletal and connective tissue disorders
Back pain
3
1
Nervous system disorders
Headache
6
5
Dizziness
5
1
Somnolence
3
1
Psychiatric disorders
Anxiety
4
3
Depression
3
1
Aggression
2
1
Renal and urinary disorders
Urinary incontinence
2
1
Vascular disorders
Hypertension
4
2
Hypotension
2
1

  • Discontinuation due to adverse reactions was 10% for the NAMENDA XR 28 mg+AChEI treatment group and 6.3% for the placebo+AChEI treatment group. The most common adverse reaction that led to treatment discontinuation in this study was dizziness, at a rate of 1.5% in the NAMENDA XR-treated group1

Drug interactions

  • No drug-drug interaction studies have been conducted with NAMENDA XR, specifically1
  • No pharmacokinetic interactions with drugs metabolized by cytochrome P450 enzymes are expected1
  • The combined use of NAMENDA XR with other NMDA* antagonists (amantadine, ketamine, or dextromethorphan) has not been systematically evaluated and such use should be approached with caution1
  • Please see full Prescribing Information for complete details on pharmacokinetic drug interactions
Important Safety Information

Contraindications

  • NAMENDA XR is contraindicated in patients with known hypersensitivity to memantine hydrochloride or to any excipients used in the formulation.

Warnings and Precautions

  • NAMENDA XR should be used with caution under conditions that raise urine pH (including alterations by diet, drugs and the clinical state of the patient). Alkaline urine conditions may decrease the urinary elimination of memantine, resulting in increased plasma levels and a possible increase in adverse effects.
  • NAMENDA XR has not been systematically evaluated in patients with a seizure disorder.
  • NMDA=N-methyl-D-aspartate.

Review efficacy in global function with NAMENDA XR 28 mg

Review efficacy in cognition with NAMENDA XR 28 mg

Learn about once-daily dosing with NAMENDA XR

References:

  1. NAMENDA XR (memantine HCl) extended-release Prescribing Information. Cincinnati, OH: Forest Pharmaceuticals, Inc.; 2014.

NAMENDA XR® (memantine hydrochloride) extended-release capsules are indicated for the treatment of moderate to severe dementia of the Alzheimer’s type.

Important Safety Information

Contraindications

  • NAMENDA XR is contraindicated in patients with known hypersensitivity to memantine hydrochloride or to any excipients used in the formulation.

Warnings and Precautions

  • Conditions that raise urine pH may decrease the urinary elimination of memantine resulting in increased plasma levels of memantine.

Adverse Reactions

  • The most commonly observed adverse reactions in patients administered NAMENDA XR (28 mg/day) in a controlled clinical trial, defined as those occurring at a frequency of at least 5% in the NAMENDA XR group and at a higher frequency than placebo were headache (6% vs 5%), diarrhea (5% vs 4%), and dizziness (5% vs 1%).
  • NAMENDA XR has not been systematically evaluated in patients with a seizure disorder.

Drug Interactions

  • Alterations of urine pH toward the alkaline condition may lead to an accumulation of memantine with a possible increase in adverse reactions. NAMENDA XR should be used with caution under conditions that may be associated with increased urine pH including alterations by diet, drugs, and the clinical state of the patient.
  • No drug-drug interaction studies have been conducted with NAMENDA XR, specifically. The combined use of NAMENDA XR with other NMDA antagonists (amantadine, ketamine, or dextromethorphan) has not been systematically evaluated and such use should be approached with caution.

Dosage and Administration

  • The recommended starting dose of NAMENDA XR is 7 mg once daily. The recommended target dose is 28 mg once daily. The dose should be increased in 7 mg increments to 28 mg once daily. The minimum recommended interval between dose increases is one week, and only if the previous dose has been well tolerated. The maximum recommended dose is 28 mg once daily.
  • It is recommended that a patient who is on a regimen of 10 mg twice daily of NAMENDA tablets be switched to NAMENDA XR 28 mg once-daily capsules the day following the last dose of a 10 mg NAMENDA tablet. There is no study addressing the comparative efficacy of these 2 regimens.
  • It is recommended that a patient with severe renal impairment who is on a regimen of 5 mg twice daily of NAMENDA tablets be switched to NAMENDA XR 14 mg once-daily capsules the day following the last dose of a 5 mg NAMENDA tablet.

Special Populations

  • NAMENDA XR should be administered with caution to patients with severe hepatic impairment.
  • A target dose of 14 mg/day is recommended in patients with severe renal impairment (creatinine clearance of 5-29 mL/min, based on the Cockcroft-Gault equation).