Participants assigned to this arm will continue to use tadalafil as prescribed per standard of care treatment and will also be instructed to use Eroxon® gel prior to each sexual encounter throughout the 12-week study period.

Participants assigned to this arm will continue their standard-of-care treatment with tadalafil as prescribed. No study-specific changes will be made to their routine clinical management.

Participants will receive a 12-week supply of Eroxon® and will be instructed to apply the gel prior to each sexual encounter as directed at enrollment.

Erectile function assessed using the International Index of Erectile Function-5 (IIEF-5), a validated 5-item patient-reported questionnaire. Total scores range from 5 to 25, with higher scores indicating better erectile function.

Patient adherence assessed using the Medication Adherence Report Scale-5 (MARS-5), a validated five-item self-report questionnaire measuring both intentional and unintentional non-adherence. Each item is scored on a 5-point Likert scale, with total scores ranging from 5 to 25, and higher scores indicating better adherence.