Memantina Vir (Memantine Hydrochloride)

• Memantine is used in the management of Alzheimer’s disease, a neurodegenerative disorder affecting cognition and function.
• Alzheimer’s disease (moderate to severe): provides modest improvement in cognition and daily living activities.
• Alzheimer’s disease (behavioral symptoms): may reduce agitation and aggression.
• Alzheimer’s disease (functional decline): helps maintain ability to perform basic self‑care tasks.

• Memantine acts as a non‑competitive antagonist at the NMDA (N‑methyl‑D‑aspartate) receptor, binding to the receptor-associated ion channel and reducing excessive calcium influx. By moderating glutamate‑mediated excitotoxicity, it helps protect neurons from damage associated with over‑activation of excitatory pathways, thereby supporting neuronal function in Alzheimer’s disease.

Memantine may cause a range of adverse reactions, most of which are mild to moderate in severity.

Common Side Effects

• Dizziness: sensation of light‑headedness or unsteadiness.
• Headache: mild to moderate pain in the head region.
• Constipation: reduced bowel movements or hard stools.
• Confusion: temporary disorientation or difficulty concentrating.
• Hypertension: elevated blood pressure readings.
• Fatigue: feeling unusually tired or low in energy.

Serious or Rare Side Effects

• Seizures: convulsive episodes requiring medical attention.
• Hallucinations: visual or auditory disturbances.
• Severe allergic reaction: rash, itching, swelling, or difficulty breathing.
• Cardiac arrhythmia: irregular heart rhythm.
• Psychosis: severe changes in perception or thought processes.
• Liver enzyme elevation: abnormal liver function tests.

Memantine requires careful consideration of patient‑specific factors before use.

• Renal impairment: assess kidney function and adjust dose if necessary.
• Hepatic impairment: monitor liver function and consider dose modification.
• Concomitant CNS disease: use cautiously in patients with epilepsy or other central nervous system disorders.
• Pregnancy: safety not established; avoid unless benefits outweigh risks.
• Breastfeeding: unknown excretion in milk; consider alternative therapy.
• Store at ambient temperature (below 25°C): keep in the original pack, protect from moisture.

Memantine may interact with other medicines, affecting its safety or effectiveness.

Major Interactions (Avoid)

• Amantadine: increased risk of neurotoxicity.
• Ketamine: additive CNS effects leading to heightened confusion.

Moderate Interactions (Monitor Closely)

• Anticholinergic agents: may reduce therapeutic benefit.
• CNS depressants (e.g., benzodiazepines): may enhance sedation.
• Diuretics: may raise plasma concentration of memantine.
• Antihypertensives: possible additive blood‑pressure lowering effect.
• Proton‑pump inhibitors: may modestly increase memantine levels.