I think I grew up on horehound cough drops. Whenever the cold season would come knocking, my mom had a bag of horehound "candy" to help ease coughing. This recipe should be made before the cough season begins so that you have it on hand when you start to develop a cough.
Horehound Cough Drop Recipe
1 cup packed, fresh horehound leaves
1 cup water
2 cups sugar
2 Tbsp honey
Boil the horehound in the water for 20 minutes. Remove from burner and let cool. Strain by placing a piece of cheesecloth inside a colander. Pour horehound tea through the lined colander and into a clean, medium saucepan. Add sugar and honey. Stir. Bring liquid to a boil. Reduce head to medium and allow to simmer. Stir constantly until the liquid reaches the hard crack stage at 300 degrees F.
While the liquid is cooking into hard candy, lightly butter a baking sheet. Set aside until liquid reaches hard crack stage. Pour the syrupy liquid onto the baking sheet and allow to cool. After it has cooled a bit, crack the sheet of "candy" into mouth-size pieces. Roll each piece in granulated or confectioner's sugar. Store in dry container or bag until needed.