LD50

Rat Oral LD 50 >800 mg/kg ^F4298.

Carcinogenicity, mutagenicity, impact on fertility

Pramipexole was not found to be carcinogenic in 2-year studies on mice and rats at 0.3, 2.2, and 11 times the maximum recommended human dose (MRHD). No increased incidence of tumors was observed ^{FDA label}. No mutagenicity was detected in various assays, including the Ames test. Finally, pramipexole given to rat models at a dose of 2.5 mg/kg/day (5 times the maximum recommended human dose), increased estrus cycles and inhibited implantation of a fertilized ovum. Decreased levels of prolactin, a hormone necessary for implantation and maintenance of early pregnancy, were measured ^{FDA label}. The significance of these findings in humans is unknown.

Pregnancy

This drug is considered a pregnancy category C drug, showing teratogenic effects in animals. Currently, there no studies of pramipexole in human pregnancy. Animal reproduction studies are not always predictive of human response. This drug should only be used in pregnancy if the potential benefit outweighs the possible fetal risks ^{FDA label}.

Nursing

Whether pramipexole is excreted in human milk is unknown. A decision should be made regarding the administration pramipexole during nursing, or whether to discontinue it during nursing, as many drugs are excreted in human milk. The potential exists for risk to the infant if pramipexole is, in fact, excreted in the milk ^{FDA label}.