When vata-vitiating substances are administered to persons indulging in overwork, sexual intercourse and exercise while kapha-vitiating ones to those who oversleep or are lazy, it is an example of antagonism with respect to health conditions.
If hot things are taken after intake of pork etc. or cold ones after intake of ghee etc. it is known as antagonism with respect to indication and contra-indication.
Antagonism in terms of cooking consists of cooking using damaged or bad fuel or if the grains are left uncooked, over-cooked or burnt. Sour things taken with milk is antagonism in terms of combination.
Antagonism in terms of palatability is taking of unlikeable things. Antagonism in terms of richness (of qualities) is that if there is immature, overmature or damaged rasa in a substance.