Suggest Treatment For Painful Boils In The Neck & Head Region

I am 38 years old. A week before I have severe throat infection , cold and cough. My doctor gave Advent 625 twice a day for 1 week. I have now started getting some boils kind in my neck and head region and they are very painful. Some mild skin infections are also appearing. Is that a side effect of tablet I took or someother issue.