LD50

Oral LD50, mouse 437-498 mg/kg ^F4375
Oral LD50, rat 328-370 mg/kg ^F4375

Carcinogenesis, Mutagenesis, Impairment of Fertility

No evidence of carcinogenicity was seen in mouse and rat models administered memantine at doses equivalent to supratherapeutic human doses ^{FDA label}. Additionally, no genotoxic potential was noted when a battery of assays was performed. No effects on fertility or reproductive performance were noted in rats given to 18 mg/kg/day (equivalent to 9 times the maximum recommended human dose) orally from 14 days preceding mating through gestation and lactation in females, or for 60 preceding mating activity in males animals ^{FDA label}.

Use in pregnancy

This drug is considered a pregnancy category B drug, meaning no sufficiently controlled and adequate studies of memantine in pregnant women have been performed. This drug should be taken during pregnancy only if the potential benefit justifies the possible fetal risk ^{FDA label}.

Use in nursing

It is unknown whether memantine is excreted in human milk. Due to that fact that many drugs are found excreted in human milk, caution should be observed when this drug is taken by a nursing mother ^{FDA label}.