Hello, I can sympathize with you. I've had those sore throat problems all my life. The only thing that seemed to work was an elimination diet, meaning I was still eating something that was causing the drainage. I started with what I knew was right. Ezekiel bread toast for breakfast and beef and fresh steamed/boiled broccoli for lunch and dinner. (Not the chinese food beef & broccoli, that has cornstarch in it). I did this for about a week, no snacks or extras unless i KNEW they were okay, such as fruits.
At the end of the week, I was able to add my usuals back in and found the culprits. Beer, hershey bars etc. When I replaced the bad things with good substitutes I noticed my problem completely cleared up.
So give this a try, it really works. And I did this without taking any supplements. It also might be this time of year, it's really bad for your sinuses. If the elimination diet doesn't work, wait a few months for the weather to straighten out.
Hope this helps, Beth (O)