Brief Answer:
Possible Pityriasis Rosea

Detailed Answer:
Thanks for contacting HCM with your health care concern

Your girlfriend is suffering with a new rash on her back that itches. I am sorry that you could not attach the picture as it would help tremendously. If you would like, you can email your pic to YYYY@YYYY , ask the team there to attach your picture to queryid: 169061.

But with your limited description is that it could be pityriasis rosea. This is a raised rash with itiching that starts with something we call a herald patch or a single patch of rash. this rash then spreads and has a Christmas tree. This is possibly caused by a virus but we are not completely sure. The treatment is to treat the itch with an antihistamine like Claritin or bathing with aveeno. The other option is contact dermatitis or allergic reaction to something against her skin. This rash will also be red raised and generally over an area without the first patch. the treatment is the same antihistamines and aveeno baths. For either condition you can also try a steroid cream like hydrocortisone.

In summary
1. Pityriasis Rosea
2. Contact dermatitis or allergic dermatitis
3. treat with antihistamine Aveeno bath and steroid creams

I hope this answers your question. Please contact HCM again with your health care concerns and questions. If you have any further questions please feel free to contact me again.

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Brief Answer:
Contact dermatitis

Detailed Answer:
Thanks for submitting the pictures the definitely help.

From the picture this looks like she has a contact dermatitis or an allergic reaction to something in contact with her skin. For this I recommend she use a steroid cream like hydrocortisone to help reduce the itch. I would also recommend placing an ice pack on the rash which will also reduce the itch. She can still take antihistamine like Claritin which will also reduce the redness and the itch.

I hope this answers your question.

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