What does “INN stem” mean for sartan angiotensin II receptor antagonists?
International Nonproprietary Names (INN) use standardized “stems” to signal a drug’s class. For angiotensin II receptor antagonists (also called angiotensin receptor blockers, ARBs), the INN stem is “-sartan.”
So drug names that end in or contain “-sartan” are typically ARB medicines that block the angiotensin II (AT1) receptor.
Which drugs use the “-sartan” INN stem?
Common ARBs with the “-sartan” stem include (examples): losartan, valsartan, irbesartan, candesartan, telmisartan, and eprosartan.
How is the INN stem useful clinically or for searching?
If you see “-sartan” in a drug name, it’s a strong indicator the medication is in the angiotensin II receptor antagonist/ARB family, which helps with:
- identifying drug class quickly when reading labels,
- searching for related medicines,
- anticipating typical therapeutic use (hypertension, diabetic kidney protection in some settings) and class-level safety monitoring (e.g., kidney function and potassium).
Any exceptions or edge cases?
In general, “-sartan” is considered the hallmark stem for ARBs. If a name does not contain “-sartan,” it usually is not an angiotensin II receptor antagonist, though other medications can still act in the renin-angiotensin system through different mechanisms.
Sources
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