Hello. Welcome to ask the doctor.
As per details, it seems that you are allergic to the plants. It may sometimes present with only itch. But with repeated exposures, the allergic reaction of the body to allergen increases. So there is a possibility that if you come in contact with the implicated allergen, the rash may appear subsequently.
Avoid such exposures.
I prefer to advise my patients oral antihistaminics like Levocetirizine for symptomatic relief.
Do not take any medication without a Doctor's prescription.
I hope it helps.
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