Suggest Remedy For Pain While Swallowing

My husband was stung by a bee last Sunday on the hand and had an allergic reaction (swelling of the hand). The doctor proscribed cortizone which reduced the swelling entirely, but on Monday my husband was bitten again, we think by a horse fly or wasp, on the back of the neck. Since this second bite, he has difficulty swallowing. He is still taking cortizone as the doctor proscribed. I am concerned about the difficulty swallowing. It is painful for him to eat or drink. When he tries to do so the pain in the insect bite on the neck increases.