Hello, I have a question in regards to my throat. I ve been having a sore throat for well over a month.. it comes and goes. My doctor prescribed me omeprazole 20 mg for acid reflux. this is my 2nd day taking the medication, throughout the day, my throat seems a little dry, something like cotton mouth but towards the night, my throat seems relieved. how long does it normally take for the omeprazole to work and also is the cotton mouth a good affect?