please help get rid off this acne/raised blemish!!

Okay so let's go back 3 months ago my skin use to be completely clea! And now I have this awful raised rash like brbrakeout around my mouth,chin and forehead and won't go away! Was using acnecide gel 5% for awhile and also Sudocrem with la Roche posay cleanser for dry skin.. honestly I think it's something I am eating cause it was cleared up pretty well and then I started eating weetabix and the rash is back out as bad as ever again!! Back when I use have clear skin (3/4months ago) I use eat weetabix with no problems?! What's going on?