Maybe not a *cure* as such but something that kicks any cold I start to get out the door quick smart is a mix I make up and sip on throughout the day.
We've been away for a few days, it was great but wet and windy and I started sneezing and had a few other symptoms so on getting home I made up my *medicine*
It's just a mixture of white vinegar, honey and lemon juice. I mix the same amount of each, give or take, and drink it down.
It doesn't always taste great but it isn't horrible and it works better than any cough medicine.
I have also made the mixture with added grated lemon zest and extra juice. Much nicer as the vinegar taste is not as strong.