chrystlek,

Thanks for your posted question.  I can find no contraindication to mixing loratadine (Claritin) and Chantix.  However, you asked about the 24 hour loratadine pill, and Claritin is meant to be taken once a day at 10 mg.  They do market a combination tablet called Claritin D 24 hour, which contains the loratadine plus a 24 hour formulation of pseudoephedrine.  This combination makes me hesitate because the side effects of the pseudoephedrine are similar to the side effects of the Chantix, as well as most of the symptoms of nicotine withdrawal.  Therefore, if you took the Claritin D 24 hour plus the Chantix, and you stopped smoking, your symptoms could be compounded, and you wouldn't know which to blame.

I suggest you not take Claritin D 12 hour or 24 hour formulas.  If you must take an antihistamine, the loratadine by itself should be OK. 

Congratulations on your attempts at stopping this dangerous habit.

Martin Cane, M.D.