Can i take only half a dose of pseudoephedrine (30mg)? i am also taking gualfenesin and dextromethorphan to aid in relieving sinus pressure....

Usually no problem: However, nasal steroids are the standard of care. G/d/p are not really useful. In my opinion they should be removed from the market. Antihistamines can also help, such as allegra.

Yes, but.: You can take 15 mg of Pseudoephedrine , or the half of the 30 mg tablet. Just make sure you do not have high blood pressure or irregular heart beat.