I get "drama sickness" after most dramas I watch. It usually lasts for a while if I feel a series finale was inconclusive or could've been better or had some loose ends (Dream High, God of Study, Baker King, IRIS). If it concludes really well, I usually only feel it for about the rest of the day (Secret Garden, Incarnation of Money, Flower Boy Next Door). I usually just start a new drama if I'm feeling drama sickness.