How do you treat swollen lips due to an allergic reaction?

Medication: Antihistamines can be very helpful. Benadryl (diphenhydramine) works well but can cause sleepiness. Other antihistamines like zyrtec, Allegra and Claritin also work well. In severe cases a doctor can prescribe oral steroids or an injection.

Swollen Lips: Consider going to an er if the swelling is persisting since you might need an Epinephrine shot and high dose antihistamines.