So you have a sore throat and need to sing?
There are a lot of products out there but some are NOT suitable for Singers as they dry out much needed mucosa - mucous (like oil in a car motor) My first recommendation would be to take, daily if you can, Manuka Honey. It has great natural properties for reducing bad bacteria, lowering the risk of cold's and sore throats. BUT if you do feel an irritation starting from a cold or flu symptom then Betadine gargle (Iodine) especially before bed, will help kill any bad bacteria and greatly reduce the risk of colds or flu taking hold. It is part of the vocalist first aid kit that I recommend and should be on hand as the earlier you take it the better chance of stopping infection taking hold.