Hello! Thank you for asking on HCM! I carefully passed through your question and would explain that pseudoephedrine can cause a raise in the heart rate as an adverse effect (it is a stimulant of sympathetic nervous system). Do you have any other symptoms like shortness of breath, dizziness, etc.? If you have no other symptoms, there is nothing to worry about. You can continue taking this. But if you have any of the above mentioned symptoms, and you do not tolerate this elevated heart rate, you can stop taking this drug. You should know that this is a symptomatic reliever, which means that it makes you feel better and helps with the congestion of the sinuses, but is not indispensable like antibiotics can be (in case of bacterial infection) Hope you will find this answer helpful! Best wishes, Dr. Iliri