Theoretically, it is possible that diphenhydramine could affect a woman's milk supply, since the medication can suppress prolactin (a hormone important for breast milk production). However, this is probably not an issue for women who are well-established with breastfeeding.
PRO is a strategic communications firm helping high profile individuals, professional teams, national governing bodies, corporations and non-profits within the sports industry build their brands through the media.
Definition of professional for Students. 1  1 : a person who does a job that requires special education or skill. 2  2 : a person who is paid to participate in a sport or activity.