Caution is recommended in 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 with Proteus bacteria.