Is Sambuca good for a common cold?

It could help a cough and help you rest, like many cough medicines do that have alcohol as an active ingredient. But you should not use more than an ounce or less at a time and not more often than you would use the cough medicines, no more often than every few hours. It would not only not be good, but could be bad, if you use more than that since alcohol is a diuretic and could contribute to dehydration. You need extra fluids when fighting a cold. Do not use alcohol along with medicines that also have alcohol as an ingredient, and read the labels or ask your pharmacist if there would be a problem taking alcohol with other medicines you take at the time.