### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
Hi I have a red itchy rash on my chest/ neck area which is now working its way up to my face. It is a pimply like rash with white heads. I have had it on and off for about 3 weeks but it has gone away on its own until now when I have had it for about a week. I have recently been on Doxycycline and stopped taking them about a week ago. Not sure if this is related or not? Thanks

### output:

Hi Going by your history, you have itching and rash involving your face, chest and neck... Now there are two possibilities ...either it can be acne lesions(acne corporal meaning pimples of body) or it can be a photosensitive rash. Acne vulgarism is a common human skin disease, characterized by areas of skin with seborrhea (scaly red skin), comedones (blackheads and whiteheads), pa pules (pinheads), pustules (pimples), nodules (large pa pules) and possibly scarring. Acne affects mostly skin with the densest population of sebaceous follicles; these areas include the face, the upper part of the chest, and the back. Some people are sensitive to sunlight; this is known as photosensitivity. Photosensitivity may produce a rash, which is known by the general term, photodermatosis. Patients may not associate their skin complaint with exposure to light. It is not always the bright summer sun which is responsible; some people also react to sunlight in winter, and very sensitive subjects may even be affected by fluorescent lamps indoors. As in your case, only the exposed sites are involved, so you need to be sure if you have any degree of itching or burning sensation on exposure to sunlight,,,,And as far as doxycycline is concerned,it is a commonly used Chat Doctor. ....but at the same time this 