Ketoconazole and Ranolazine Interaction

Drug interaction information between Ketoconazole and Ranolazine.

Ketoconazole and Ranolazine have a documented major interaction in FDA labeling.

FDA drug labeling documents a major-severity interaction between Ketoconazole and Ranolazine. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.

Drug A

Ketoconazole

Azole Antifungal

Drug B

Ranolazine

Late Sodium Current Inhibitor (Antianginal)

How They Interact

Ketoconazole stops the body from breaking down ranolazine, which can cause the drug to build up to unsafe levels in your blood.

FDA Label Information

( 7.2 ) 7.1 Effects of Other Drugs on Ranolazine Strong CYP3A Inhibitors Do not use ranolazine with strong CYP3A inhibitors, including ketoconazole, itraconazole, clarithromycin, nefazodone, nelfinavir, ritonavir, indinavir, and saquinavir [see Contraindications (4) , Clinical Pharmacology (12.3) ].

Frequently Asked Questions

What SPL severity band is on file for Ketoconazole + Ranolazine?

Compiled FDA labeling labels this pair major. That is a source-record field, not an individual medication-combination decision.

Which drug in this pair has the larger labeled-interaction portfolio?

Ketoconazole has 113 labeled pairs on file vs Ranolazine's 31. In the major band specifically: Ketoconazole has 6 (also Alfuzosin, Dronedarone, Saxagliptin, Sildenafil); Ranolazine has 12 (also Carbamazepine, Clarithromycin, Rifampin, Phenytoin).

What mechanism field is on file for Ketoconazole and Ranolazine?

Ketoconazole stops the body from breaking down ranolazine, which can cause the drug to build up to unsafe levels in your blood.

Ranolazine carries more major-labeled pairs than Ketoconazole

SPL source-record counts only. This page's band is major · classes on file: Ketoconazole (Azole Antifungal); Ranolazine (Late Sodium Current Inhibitor (Antianginal)).

Ranolazine has 12 major-labeled pairs vs Ketoconazole's 6.

Ketoconazole

6 major · 22 moderate · 85 minor · 113 total

Ranolazine

12 major · 7 moderate · 12 minor · 31 total

Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.