Hello Doctor. I recently recovered from Covid (RT-PCR negative) but I still have some cough. Sometimes it's sore throat cough and other times it contain phlegm. I still do gargling and steam once or twice a day. It would be great if you can suggest a cough syrup as I'm not having any. I would also like to know how is Benadryl for covid cough? Also what food should I avoid in cough? Thank you.