The phrase "taste of one's own medicine" means experiencing the same kind of treatment or action from others that you have previously given to them. Full definition
In the case of Comrade Jacob Zuma, let us just say that he was given a bitter taste of the medicine he fed to Comrade Thabo Mbeki about a decade ago when he led the African National Congress (ANC) to show the MIGHT of the Party and oust Mbeki as Leader; and went on to force him out as President of South Africa. (ghanapoliticsonline.com)
If we start like we did against Newcastle they won't know what hit em, pace pace pace just like they did to us round, so let's give them a taste of their medicine. (justarsenal.com)
I don't find his comment or reaction as a surprise cos that is what he's good at MOANING and COMPLAINING... When Man Utd came to the bridge last season and outplayed his team in every department bar goal scored, he came out to say it was a tactical genius on his part even when LVG was complaining... whenever he's given a taste of his medicine he ALWAYS moans. (justarsenal.com)