Lenin

Guaifenesin is ok to use if you like its effects. Coricidin on the other hand is a rather catch-all term for a whole line of cold medications, some for night time, some for day time, some for cough, some for congestion.
Make sure you are getting one WITHOUT a decongestant.
I use guiatuss when I have a bad cough it has guiafenesin and codeine (the very BEST anti cough narcotic.) I wish I could get it WITHOUT the guiafenesin but nobody makes plain codeine syrup and the old codeine terpenhydrate combo which was WONDERFUL just isn't made anymore, alas...It also tasted like a very good GIN!
Guaifenesin makes me cough more...it's an expectorant, and I don't like the effect one bit.

Another ingredient that hypertensives can use is chlorpheniramine which is an antihistamine, goof for sneezing and watery eyes...and also another sleep aid.
"Coricidin HBP Cough and Cold" has two ingredients, dextromethorphan for cough and chlorpheniramine antihistamine...no guaifenesin. The Flu formulation adds acepamenophen (Tylenol.)

Unfortunately a snuffy nose will have to be borne with stoicism...all the decongestants raise BP a lot. If DESPERATE use nose drops which deliver the medication to the clog is rather than throughout the whole body...but using nothing is the wiser alternative.

I felt like babbling on about the subject because my other half is coughing up a storm and I am JUST beginning to feel a little "something" in my chest.
Merry Christmas.