Medication Pearl of the Day: Memantine HCl (Namenda)
Indication: Memantine HCl(Namenda) is an N-methyl-D-aspartate (NMDA) receptor antagonist indicated for the treatment of moderate to severe dementia of the Alzheimer’s type.
Insight:
- Dosing: Initial dose is 5 mg once daily. Increase dose in 5 mg increments to a maintenance dose of 10 mg twice daily. A minimum of 1 week of treatment with the previous dose should be observed before increasing the dose.
- Dosage forms: Tablets 5 mg and 10 mg. Oral Solution 2 mg/mL.
- Adverse events: Most common adverse reactions (≥ 5 % and greater than placebo) are dizziness, headache, confusion, and constipation.
- Mechanism of action: Persistent activation of central nervous system NMDA receptors by the excitatory amino acid glutamate has been hypothesized to contribute to the symptomatology of Alzheimer disease. Memantine is postulated to exert its therapeutic effect through its action as a low to moderate affinity uncompetitive (open-channel) NMDA receptor antagonist, which binds preferentially to the NMDA receptor-operated cation channels.
Source: label (fda.gov)