Hi, I understand your concern Plan B hass various side effects like allergy, nausea,dizziness, diarrhea,head ache, change in menstrual pattern,breast tenderness etc. The rash you have on your lower abdomen ,if accompanied by itching, can be an allergic reaction. -If you start getting difficulty in breathing/ swelling on face,lips,tongue along with the rash, you have to rush to doctor- for it s a sign of severe allergy. _ only rash with itching can be managed by Tab, cetrizine after food at bed time, Betnovate ointment locally- for 3-5 days. Please get it confirmed by your doctor. Thanks.