 [ Symptoms ] if my son is currently receiving chip should i apply anyway as chip expires from him in april 2014 [ Disease ] you have not been on one medication long enough for it to get into your system to work diphenhydramine the active ingredient in antihistamines like benadryl would be a last resort due to the side effects that include a hangover feeling dry mouth constipation and dizziness do you tune into your weather forecast to check the pollen counts if they are high you will continue to have your symptoms stay on one product during the allergy season and if after a week or so you do not seem to be getting better see your doctor or health care provider you may need prescription medication this is an example of something you can talk to your pharmacist about