Can i take benedryl for itching due to dental pain and facial edema?

Yes: For itch, not for pain.

I don't see why not: Benedryl shouldn't make the situation any worse. Just make sure you get treated for the infection.

Allergy/infection: Itch usually means allergic reaction. Pain and swelling usually means an infection that is getting out of control. Benedryl may reduce the itching , but will not eliminate the allergy. Nor will it treat infection. Before this gets out of hand please call our dentist. Treat the cause of the pain/swelling/itching...Don't just mask the symptoms.

NO: Dental pain and facial edema are an infection. Itching may be unrelated. See dentist for dental infection.