DDI

Medical abbreviation · Pharmacology

DDI
Stands forDrug-drug interaction
CategoriesMedical

DDI stands for Drug-drug interaction, a pharmacology abbreviation.

Change in the effect or blood level of one drug caused by another, through mechanisms such as enzyme inhibition, enzyme induction, transporter effects or additive pharmacology. Pharmacy systems screen every new prescription for DDIs.

Example: DDI alert: clarithromycin with simvastatin raises rhabdomyolysis risk; hold statin.

Usage notes

Interactions are usually ranked by severity, from minor to contraindicated combinations. Many involve CYP enzymes; for example, rifampin induces CYP3A4 and can make oral contraceptives or tacrolimus ineffective. Alert fatigue, where clinicians override most warnings, is a recognized safety problem with electronic DDI screening.

More pharmacology abbreviations

  • BBW – Black box warning
  • BE – Bioequivalence
  • Cmax – Maximum concentration
  • Css – Steady-state concentration
  • CYP – Cytochrome P450
  • DDD – Defined daily dose
  • DLT – Dose-limiting toxicity
  • ED50 – Median effective dose
  • INN – International Nonproprietary Name
  • LD50 – Median lethal dose
  • MOA – Mechanism of action
  • MTD – Maximum tolerated dose

See all 36 pharmacology abbreviations →

Edited by the AbbreviationList.com team. Spotted an error or a missing meaning? Contact us.

This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.