DS (almost 12 yrs old) has been coughing nonstop for 2 weeks, tickly unproductive cough, nose a bit blocked, sneezing occasionally. Doctor suggested antihistamine, been taking Cetirizine (Benadryl) for 3 days but no effect whatsoever. No real interest from medical profession as he is well in himself and no fever etc. Anyone else have similar experience, and can anti-histamine take a few days to have an effect? Poor boy is waking up 4-5 times a night every night with cough.