Hi,

Thanks for posting your query

According to your description there are two possibilities
1) Contact Irritant Dermatitis - Rash and itch with slight swelling.
2) Insect bite which presents with associated redness,pain,swelling are the common complaints after a bite. You can check for bite XXXXXXX

You can apply Calamine lotion for both of the above conditions twice a day. You can also give a Tylenol Kid for the swelling to subside thrice a day.

Some other supplemental measures for you:
Wash the area with antibacterial soap and water.
Apply ice pack wrapped in cloth several times so that swelling is reduced.
You can give any oral antihistamine as Benadryl for relief from allergy.

The symptoms should subside in 2 to 3 days but if the pain and swelling increases or does not subside at all then consider visiting your Healthcare Provider for evaluation as sometimes steroid ointments and other prescription medications might be required.

Hope I have answered your query.I will be available for follow up if any.

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