Generic name for zyrtec?

What is the generic name for Zyrtec?

Zyrtec’s generic name is cetirizine. [1]

What medicine is Zyrtec compared to (brand vs generic)?

Zyrtec is the brand name; cetirizine is the active ingredient used in both brand and generic versions. [1]

Is Zyrtec also sold as “cetirizine” in different strengths?

Yes. Generic cetirizine products are marketed in common adult and pediatric strengths, depending on the formulation (tablets, chewables, or liquid), but the active ingredient stays cetirizine. [1]

Sources:
[1] https://www.drugs.com/zyrtec.html