If you experience chronic constipation, or if eating prunes and drinking prune juice doesnât solve your problems, contact your doctor for professional advice. Also, make sure to talk to your doctor if you begin to experience: 1  rectal or abdominal pain.  blood in stool.
agonist agÂ·oÂ·nist (Äg'É-nÄ­st) n. A contracting muscle that is resisted or counteracted by an antagonistic muscle. A substance that can combine with a cell receptor to produce a reaction typical for that substance.
Medical Definition of Antagonist. Antagonist: A substance that acts against and blocks an action. Antagonist is the opposite of agonist. Antagonists and agonists are key players in the chemistry of the human body and in pharmacology. Last Editorial Review: 5/13/2016.