This is dangerous when you have neck swelling. Have you been to the doctor? You may need steroid help. In the meantime anti inflammatory like Motrin, continue with benadryl, if too sleepy with benadryl you can try a different antihistamine but benadryl is best. Ice can help with swelling. I have seen icthamol (used on horses) help as an old farmhand cure but will not swear by it (and the stuff smells really bad).
2014 Crew Cab Chevy Silverado 3500 4wd Duramax/Allison
2014 Sabre 34REQS-6