hello and welcome to health care magic, You are very clever and right in asking this question about Pseudoephedrine. Although it is a relatively safe medication it is known with lots of side effects and in fact its combination with antihistamine has been banned in many countries. In any case I would advice you to not to listen to the pharmacist and get a proper ENT consult as when it comes to health you should never compromise. I do agree many pharmacists have an extensive knowledge of drugs, they can never have the clinical experience which the doctor is trained in from his first year. These include the effects of medications and the interactions which is the basic knowledge for any doctor. So get a proper advice get well soon regards Dr Sriram Nathan