MVP and Claritin D

Due to the severity of my allerigies, I have to take Claritin D, every day,  24/7.  It helps keep me going, as I do not feel any of the heart palpatations from my mitral valve prolapse, and the medication also keeps me more alert and less tired so that I do not feel as sluggish from my hypothyroidism.  What, exactly, is the ingredient or main component in Claritin D that seems to mask the symptoms of the MVP?  Is this medication safe for me to take daily with my MVP condition?  It doen't seem to be considered a Beta Blocker, but it seems to react in my body like a Beta Blocker would?  Any comments you have on this would be deeply appreciated as none of my Physicians seem to be able to asnwer these questions.

[Momto3]

Claritin D (generic: Loratadine/Pseudoephedrine 24-Hour Sustained-Release Tablets) is an antihistamine and decongestent.  It's interesting that your palpitations are quieter while on this medication.  Pseudoephedrine can cause palps in some people.  It is definitely not a beta blocker and is not a medication typically used for cardiac symptoms.

Do you have symptoms from MVP?  Or, is it possible that you have MVP and symptoms (palps, etc) that are unrelated to the MVP?

Connie