Montelukast
"This medications was given to me after blue cross and blue shield stop covering levocetirizine which i had taken for 7 years. Singulair is awful.  Within 2 days i had nightmares so very vivid that was scary. The dreams would come in few minutes intervals during hours and hours of not being able to sleep at all. By the third day i had tremors in my legs which kept me awake anyways, during the day I thought about nothing then kill myself. By the fourth day  i broke out in hives. That's when I stopped it. I would not recommend!  I am very healthy athletic person and I love outdoors,  this medication was debilitating."