Are there any long term effects to taking zyrtec (cetirizine) everyday?

No, but rarely yes.: Zyrtec (cetirizine) is pretty well-tolerated and now is over the counter. You should check with your doctor if you have known liver disease or experience difficulty breathing, seizures, or low blood pressures.

Not likely: Zyrtec (cetirizine) is a new generation antihistamine approved for use in children and adults for the treatment of allergic rhinitis and hives. Zyrtec (cetirizine) is safe for long term use. A good question to ask is why is it needed everyday. Consider seeing an allergist to assist in identification of the allergic trigger and with avoidance, a person may require less medication.