This is Dr Basu, experienced Internal Medicine Specialist.
I am here to address your concerns and provide great service.
Since benadryl helps, that suggests you still have allergic reaction, or you have a condition called angioedema.
Angioedema can be hereditary due to the deficiency of C1 esterase inhibitor.
This should be checked.
Medications also can cause this if you on any.
Oral prednisone course will help to weed out any residual swelling.
You should be on combination antihistamine Claritin and Ranitidine daily to prevent such reactions.
You can continue with benadryl every 8 hours as needed.
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