urticaria
"As someone who uses Zyrtec as one of 2 primary treatments (The other being Benadryl.) I can vouch that Zyrtec gets the job done as described. 24 hours of itch free and low-drowsiness is very suitable for me. If you are someone having withdrawals from Zyrtec then you don't take it right. It only occurs when your body needs the Zyrtec in order for your brain to be chemically balanced. This usually occurs if you take it based on a schedule rather then when you notice your real symptoms. 
If you listen to your doctor and/or the label, then you will be like me as someone who is happy to be symptom free."