Anti-dementia drugs. Memantine.
There is increasing evidence that malfunctioning of glutamatergic neurotransmission, in particular at N-methyl-D-aspartate (NMDA)-receptors, contributes to both expression of symptoms and disease progression in the neurodegenerative dementia. Memantine is a voltage-dependent, moderate-affinity uncompetitive NMDA-receptor antagonist. Memantine modulates the effects of pathologically elevated tonic levels of glutamate that may lead to the neuronal dysfunction.
Mild to severe Alzheimer's disease.
Caution is recommended in the patients with epilepsy, former history of convulsions or patients with predisposing factors for epilepsy.
Concomitant use of N-methyl-D-aspartate (NMDA)-antagonists such as amantadine, ketamine or dextromethorphan should be avoided. These compounds act at the same receptor system as memantine, and therefore adverse reactions (mainly central nervous system (CNS)-related) may be more frequent or more pronounced. Some factors that may raise urine pH, may necessitate careful monitoring of the patient. These factors include drastic changes in diet, e.g. from a carnivore to a vegetarian diet, or a massive ingestion of alkalizing gastric buffers. Also, urine pH may be elevated by states of renal tubular acidosis (RTA) or severe infections of the urinary tract caused by Proteus bacteria.
In most clinical trials, patients with the recent myocardial infarction, uncompensated congestive heart failure (III−IV grade) or uncontrolled hypertension were excluded. As a consequence, only limited data are available and patients with these conditions should be closely supervised.