Hello,
Thanks for writing to us,
Catapillar is a construction company, if I am correct.
You mentioned developing the itch after working at engine blocks.

According to my knowledge, it is an allergic contact dermatitis to oil or any other material to which you came in contact while working.

I would like to know,
Whether there are any rashes also or there is only itch?
Is it only at bedtime or increased at bed time, allergic itch will be there always, but is noticed more before sleeping as at that time a person is not busy in other work.

Here are my suggestions for you..

Use calasoft lotion (calamine + liquid paraffin) twice daily.
Take an antihistamine tablet like cetrizine once daily.

Don’t take this on and off, take this for at least a month continuously, surely you will relief.

Feel free to ask any further doubt.

Wishing you good health.

Thank you

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