Although formal studies involving pregnant women have not been conducted, dopamine precursors such as levodopa (also called L-Dopa) have been shown to cause problems in the offspring of animals. In these studies, pregnant animals received several times the dosage used in humans. This affected the baby’s growth both before and after birth. As a result, women who are pregnant or who may become pregnant are urged to consult their physician before taking dopamine precursors.

Dopamine precursors pass into breast milk and may cause side effects in nursing babies. They also may reduce the flow of breast milk. As a result, these drugs should not be used by women who are breastfeeding without a physician’s approval.