Thanks to HCM I can understand your concern surprising ,it is too late abscess under armpit is painful and feel discomfort but anyway culture report shows the sensitivity so if not subside better you need to take I.V antibiotics to control the infection moreover we have to find root of infection also .. better have once CBP. ESR, CHEST X RAY once along with serum creatinine and RBS .. OK Take fruits and healthy diet , try to avoid unhygienic condition in armpit region by avoiding sweating etc wear loose cotton dresses . ok don t worry it will subside ..