Brief Answer:
Oral and topical corticosteroids

Detailed Answer:
Hello
Thank you for posting on HCM
From your description and picture, it seems you have got an acute dermatitis due to excessive itching post sunburn. It doesnot look like psoriasis because psoriasis is a chronic disease and doesnot sprout up so suddenly and more over clinically it is usually covered with thick white scales and rarely there is any associated itching.
If I was your treating dermatologist, after thourough examination and history, I would recommend application of potent corticosteroid halobetasol in combination with fusidic acid twice a day over affected areas. Also I would prescribe some antihistaminics to control itching. If after one week the reaponse is sub-optimal,I would additionally consider oral corticosteroids for 2 weeks in tapering dose.
Thus, I would recommend you to plan a consult with your dermatologist and discuss in detail the treatment I outlined.
Avoid pricking/scratching or picking of lesions.
Let me know if you require any more assistance from my side.
Thank you
Take care
Dr Hardik Pitroda

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Brief Answer:
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Detailed Answer:
Hello again,
I am afraid in USA you wont be able to get Halobetasol and fusidic acid combination cream and oral corticosteroids without prescription. You might get a weak steroid like hydrocortisone as OTC but I think it would be not be enough to take care of the condition.
Thus the best option for you is to consult a dermatologist and ask for the medications I suggested.
For itching you can get OTC BENADRYL tablets/capsules and can be taken twice or thrice a day as required to relieve itching.
Additionally apply a good quality moisturiser like Cetaphil moisturizing lotion which I think you can get OTC.
Hope you will get well soon.
Thanks
Dr Hardik Pitroda

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