Brief Answer:
details below

Detailed Answer:
Hi,
Thanks for writing to us.
The cause for itching could be urticaria, contact dermatitis/allergy, eczema, dry skin, systemic diseases like thyroid disorders/liver disorders/kidney disorders.
If it is of acute onset, acute urticaria could be the most possible cause. I would advise that you meet a dermatologist to diagnose the disease and suggest appropriate treatment.
In the interim, you may take tablet levocetirizne( 10mg) twice daily. Also use a good moisturiser to keep the skin well hydrated and apply a steroid cream like mometasone to alleviate itching.

To help further with your query, please let me know
Since how long are you having it.
Areas affected
Any history of prolonged sun exposure, new drug/medicine/ allergen.
Any history of systemic diseases like thyroid/liver or kidney disease
If your skin is dry and flaky
Answer these queries and we may continue the discussion further

Take care

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