Hello.

Thank you for the query.

I would like to know few more things which would help me in suggesting you better:

1.) Since how long are you having this problem?
2.) Do you have a red swollen rash there?
3.) Do you have similarly affected areas anywhere else on your body?

Your history suggests you have Contact dermatitis which is Inflammatory and allergic reaction to a offending agent. The offending agent has to be eliminated after finding out. Kindly get yourself examined by a Dermatologist so that he/she may examine you and run few tests like,

1.) Bloodwork.
2.) Patch test.

I don't find any relation of this itching with your operated Hernia.

Once the cause is confirmed after examination, you will treated accordingly with steroid medications and anti itch medications, both topically and orally.

In addition to this, follow these lifestyle modifications:

1.) Wear smooth textured cotton clothing, this will avoid skin irritation.
2.) Apply cool and wet compresses to the affected area.
3.) Avoid scratching as much as possible. Trim your finger nails, wear a cotton glove in the night. If you can't keep yourself from itching, apply a dressing or bandage to the rash.
4.) Avoid washing clothes using soaps and detergents which aggravate your symptoms.
5.) Stick to your treatment plan and go for regular follow up.

Hope I have answered your query, I will be available to answer your follow up query.

Regards.

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