tessalon is a prescription cough suppressant. it can cause some drowsiness so you should avoid other medications that can make you drowsy. and since it is a cough suppressant you should probably avoid other cough suppressants such as dextromethorphan. if you are worried about other specific drug interactions you should talk to your pharmacist who knows all the medications you take and can help you further.
are there any drug interactions i should be concerned with while i am taking tessalon?