Allegra or some other fexofenadine. I have persistent eczema on my upper lip that does not respond to anything except taking Allegra for 5+ days at a time. Upon stopping medication it returns.
You can try using a topical corticosteroid cream like hydrocortisone 1% on the affected area to reduce inflammation and itching. Make sure to follow the recommended dosage for Allegra and consult with your doctor if you have any concerns.