NTI
Medical abbreviation · Pharmacology
| Stands for | Narrow therapeutic index |
|---|---|
| Categories | Medical |
NTI stands for Narrow therapeutic index, a pharmacology abbreviation.
Description of drugs whose effective and toxic doses are close together, so small changes in dose or blood level can cause treatment failure or serious toxicity. Warfarin, digoxin, lithium, phenytoin, levothyroxine, tacrolimus and carbamazepine are common examples.
Example: Several states restrict substitution of NTI drugs without notifying the prescriber.
Usage notes
The FDA treats NTI drugs with tighter bioequivalence limits in some product-specific guidances, and some states require prescriber or patient consent before switching NTI generics. Switching between manufacturers is often followed by a blood level check. The term is used interchangeably with "narrow therapeutic range".
Related abbreviations
More pharmacology abbreviations
- DLT – Dose-limiting toxicity
- ED50 – Median effective dose
- INN – International Nonproprietary Name
- LD50 – Median lethal dose
- MOA – Mechanism of action
- MTD – Maximum tolerated dose
- OIC – Opioid-induced constipation
- OIH – Opioid-induced hyperalgesia
- P-gp – P-glycoprotein
- PD – Pharmacodynamics
- PGx – Pharmacogenomics
- PIM – Potentially inappropriate medication
See all 36 pharmacology abbreviations →
This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.