Goldenrod is excellent for cough and congestion. It’s naturally sweet as well. Ginger root has been a standard in cold teas in my family for generations now.

Ginger 🫚 and turmeric could also be added.

You have a lot of flora and fauna in your digestive system which your health depends upon, and which the honey will kill. I'd use Stevia.

Once I was living in a place where there was nothing open at night to go buy a cough syrup. So I thought about what is usually in cough syrup. Alcohol. I had some plum wine that someone had given me. I drank a shot sized glass of it and it did the job. Since then, on the rare occasions when I have a bad cough, I down a spoon sized portion of some sweet wine or sweet liquor. It works.