I'd look in to pertussis too! For regular coughs a ginger tea works wonders for me. Simmer fresh ginger, minced, for about 20 minutes, strain, add some honey, fresh lemon and drink like a tea. Elderberry syrup is also good. You can buy this premade, or make your own: 1/2 c. dried elderberries (I get mine from a local health food store), 3 c. water, simmer 30-45 minutes. Mash berries in the water, strain and add 1/2 the amount of honey as there is liquid left. Store in a sterilized jar in the fridge and take 1 T. ever 2-3 hours. Sometimes adding 1/2 c. organic dried thyme to the simmering process is great for a cough too.