Brief Answer:
no known interactions

Detailed Answer:
HI, thanks for using healthcare magic

There are no known interactions.

There are different formulation of mucinex.

It may contain only a mucolytic (medication to break up mucus)- guaifenesin or may contain one or more of the following

A decongestant- phenylephrine or pseudoephedrine
Cough suppressant- dextromethorphan
Pain and fever- acetaminophen
Antihistamine such as fexofenadine (Allegra)


There are no known interactions of any of these agents with zyrtec.

The use of a topical nose spray would help best along with the medication that you are using.
They are used in persons with post nasal drip eg nasonex, nasocort, flonase, rhinocort.

You may need a prescription for one of these agents.

I hope this helps, feel free to ask any other questions

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Brief Answer:
main cause

Detailed Answer:
HI

Allergies are the main cause of post nasal drip. Other cause, if symptoms occur in the short term, would be the cold/flu.

If you can pin point the source of the allergies then avoiding it would also help.

Had a patient who did allergy testing and found out she was getting her drip mainly in response to bananas.

Please feel free to ask any other questions

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Brief Answer:
if blood test, GP may be able to send off for you

Detailed Answer:
HI


Allergy tests can be in the form of skin prick testing or a blood tests to check for the response to different allergens.

If you prefer the blood test, your doctor may be able to take the sample and send it to a lab that he or she uses .

If choose skin prick testing , then either an allergist or possibly a dermatologist , may be able to do this for you.
This involves, slight pin pricks of the skin with different allergens , monitoring to see response

If anything else unclear, let me know

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