Related Experiment Video
Updated: Jun 3, 2026

An Experimental Paradigm for the Prediction of Post-Operative Pain (PPOP)
Published on: January 27, 2010
Phenazopyridine does not improve catheter discomfort following gynecologic surgery
Charles Anderson1, Maryann Chimhanda, Jayme Sloan
1Department of Obstetrics and Gynecology, Loyola University Medical Center, Maywood, IL, USA.
Objective:
We sought to determine if phenazopyridine improves pain in catheterized patients recovering from gynecologic surgery.
Study Design:
This trial randomized 240 adult women, who were undergoing gynecologic surgery and requiring an indwelling Foley catheter, to placebo or phenazopyridine hydrochloride. Group assignment was masked by instillation of orange dye in the Foley bag of both groups. The primary outcome was the mean postoperative visual analog score (VAS). Secondary outcomes were pain medicine utilization and blinding efficacy.
Results:
In all, 219 patients received study medications (112 phenazopyridine and 107 placebo). There was no significant difference in demographics, procedure type, bladder VAS, overall VAS, and pain medication use. Only 25 of the 45 participants who responded guessed their group assignment correctly, suggesting adequate blinding.
Conclusion:
Postoperative VAS scores and pain medicine usage did not change with using routine phenazopyridine following gynecology surgery. Colored dye adequately masks visual side effects of phenazopyridine.
Related Concept Videos
Urinary Tract Infection III: Diagnostic Studies and Interprofessional Care
Chemotherapy-Induced Nausea and Vomiting: 5-HT3 Receptor Antagonists
Cardiac Catheterization IV: Nursing Management
Peripheral Artery Disease V: Postoperative Nursing Management
Suctioning the Nasopharyngeal Airway
Equipment Required
Drugs for Treatment of Diarrhea-Predominant IBS
Two specific drugs used in the treatment are alosetron (Lotronex) and eluxadoline (Viberzi). Alosetron, a 5-HT3 antagonist, works by slowing the movement of stools in the gut, reducing bowel...