Allergies
"I feel absolutely horrible.  I ran out of Zyrtec, my son takes this so I figured I&#039;d try it.  On day two I feel a combination of having a concussion and a hangover all at one time.  I&#039;m fatigued, dizzy, and have a headache. This does not include the pressure I feel in my sinuses.  I feel absolutely horrible.  I&#039;m done, I won&#039;t take this again.  I&#039;m honestly not even sure the FDA should have approved this drug."