Sildenafil and Itraconazole Interaction

Drug interaction information between Sildenafil and Itraconazole.

Sildenafil and Itraconazole have a documented major interaction in FDA labeling.

FDA drug labeling documents a major-severity interaction between Sildenafil and Itraconazole. 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

Sildenafil

PDE5 Inhibitor

Drug B

Itraconazole

Azole Antifungal

How They Interact

Itraconazole stops the body from breaking down sildenafil, which can cause the drug to build up to higher levels.

FDA Label Information

7 DRUG INTERACTIONS Sildenafil can potentiate the hypotensive effects of nitrates, alpha blockers, and anti-hypertensives ( 4.1 , 5.5 , 7.1 , 7.2 , 7.3 , 12.2 ) With concomitant use of alpha blockers, initiate sildenafil at 25 mg dose ( 2.3 ) CYP3A4 inhibitors (e.g., ritonavir, ketoconazole, itraconazole, erythromycin): Increase sildenafil exposure ( 2.4 , 7.4 , 12.3 ) Ritonavir: Do not exceed a maximum single dose of 25 mg in a 48 hour period ( 2.4 , 5.6 ) Erythromycin or strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, saquinavir): Consider a starting dose of 25 mg ( 2.4 , 7.4...

Frequently Asked Questions

What SPL severity band is on file for Sildenafil + Itraconazole?

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?

Itraconazole has 116 labeled pairs on file vs Sildenafil's 10. In the major band specifically: Sildenafil has 6 (also Ketoconazole, Erythromycin, Darunavir, Hydralazine); Itraconazole has 19 (also Isavuconazonium, Lurasidone, Pimozide, Methadone).

What mechanism field is on file for Sildenafil and Itraconazole?

Itraconazole stops the body from breaking down sildenafil, which can cause the drug to build up to higher levels.

Itraconazole carries more major-labeled pairs than Sildenafil

SPL source-record counts only. This page's band is major · classes on file: Sildenafil (PDE5 Inhibitor); Itraconazole (Azole Antifungal).

Itraconazole has 19 major-labeled pairs vs Sildenafil's 6.

Sildenafil

6 major · 1 moderate · 3 minor · 10 total

Itraconazole

19 major · 20 moderate · 77 minor · 116 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.