Hi there... I couldn't find anything about why this drug may have been discontinued, but I can tell you that it is very similar to a number of other cold & allergy products commonly available. Some decongestants have been discontinued recently because of both side effects and illegal abuses of the drug.   My advice is to talk with your doctor or pharmacist about the best substitute for your needs. I'm sure you can find something that will work as well for you. But do remember that some allergy medicines can take up to a week or more to reach their full effectiveness, so you may need to give any new medicine you try a chance to work on you.   Best, Kathi