Brief Answer:
Possible dry skin. It is common in the winter, in your age.

Detailed Answer:
Hello,

Thank you for using Healthcaremagic to post your health query.
I read carefully your question and I understand your concern.

-- One common problem that happens in your age is dry skin. So my main recommendation to avoid the itchiness long term is to avoid showering in hot water (but as warm as possible) and to avoid showering often. In this way you will prevent removing the natural oils of the skin and therefor will prevent dry skin.
-- Also, apply a natural butter or oil for the skin each time after showering.
-- Have someone to have a look at your back and send me a photo if you see any lesion or anything unusual, so I can evaluate and see if you need any medicine. But as you are explaining it, seems only dry skin.
-- Drink plenty of water.

If worse or not better, I would recommend seeing a local doctor.

Hope this is helpful.
Looking forward to your follow up question in case you have any lesion in the back
Otherwise please close and rate the answer.

Regards,
Dr. Papaqako

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