Brief Answer:
Polymorphic light eruption

Detailed Answer:
Hello,
Welcome to healthcare magic.

I understand from your query that you are having itchy rashes on your neck and back.

I have seen the clinical pictures attached.

I would consider the possibility of an allergy called "Polymorphic light eruption". This is an allergy to the UV radiation of the sun.

This could also occur as a drug reaction if you are ingesting some drugs which could make the skin sensitive to sunlight. If you are on any other medications for any other problem, do let me know.

You could follow the following suggestions-

1. You could apply a cream containing Mometasone furoate ( e.g- Momate cream) twice a day for 10-14 days.
2. You could also take an antihistamine like Levocetrizine 5 mg orally at bedtime for 5-10 days.
3. You need to apply a sunscreen with broad spectrum UV protection every 3 -4 hours even if you are indoors or even if it is cloudy. Once you develop this allergy, you will be prone for such rashes even after 2- 3 minute sun exposure. So, you need to use the sunscreen very strictly on all the sun exposed areas.
4. In addition to the sunscreen, physically cover yourself or use an umbrella while going outdoors.

Hope this helps you.

If you have any more queries, I will be glad to help.

Take care,
Dr. Johny Chacko

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