What should I do for allergies if anti histamines don't work? I have persistent coughing but no other allergic reactions. I have tried alegra, claratin, and singulair (montelukast).

You. You should see an allergist and make sure that the cause is allergy for which you may need another form of medication, asthma, or another cause of cough either reflux or an infectious process among the other sources for this process.
I. I recommend seeing your local allergist. There are many causes for a persistent cough. Your allergist can determine if you have allergies, evaluate your pulmonary function and offer addition recommendations to help treat your cough.