Hi I Have A Rash That Is Driving Me Crazy

Hi I have a rash that is driving me crazy which I am sure I picked up from agapanthus plants a few days ago. I went to the doctor yesterday who gave me some ointment called "Advantan Fatty Ointment 0.1% (Methylprednisolone) and 24 hour antihistamines. The rash is raised and I aren't getting any relief from it whatsoever. It is on my neck in a big red area around my aadams apple area in the size of a tennis ball. There are also other little rashes breaking out on my chest and a couple on my arms. The ointment the doc prescribed is not helping the rash (itching) please help!