On montelukast for chronic post nasal drip. helping after 2 wks (less secretions), but feeling extremely anxious at times. side effect and common?

Yes and no: It can happen with that med but very unusual. If from this, it usually goes away after 6-8 weeks

Drug not for that.: Montelukast works as a leukatriene-receptor antagonist in yr lungs. If U are coughing secondary 2 a post nasal drip then it might help by reducing yr coughing. It doesn't deal with the drip per se, just the cough secondary yo the drip.