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Viagra in the Treatment of Primary Dysmenorrhea

This study has been completed.
National Institutes of Health (NIH)
Information provided by (Responsible Party):
Richard S. Legro, M.D., Milton S. Hershey Medical Center Identifier:
First received: July 20, 2005
Last updated: November 18, 2015
Last verified: November 2015
The primary hypothesis is that a 100mg single dose of sildenafil citrate (Viagra) will have a higher improvement rate when compared to placebo in the treatment of moderate to severe primary dysmenorrhea.

Condition Intervention Phase
Drug: Sildenafil Citrate
Drug: Placebo
Phase 1
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single Blind (Participant)
Primary Purpose: Treatment
Official Title: Sildenafil Citrate in the Treatment of Primary Dysmenorrhea

Resource links provided by NLM:

Further study details as provided by Milton S. Hershey Medical Center:

Primary Outcome Measures:
  • The Primary Outcome Was Total Pain Relief Over 4 Hours (TOPAR4), Comparing a Single Dose of Sildenafil 100 mg to a Single Dose of Placebo. [ Time Frame: Hours 1, 2, 3 and 4. ]
    The Total Pain Relief (TOPAR) Scale rates the level of pain relief on a scale of 0=None, 1=Mild, 2=Moderate, 3=Excellent, 4=Complete. The TOPAR scale was completed each hour after administration of study drug for a total of 4 hours. The 4 hourly scores were summed for a final TOPAR4 score that ranged between 0 and 16, with higher values indicating greater pain relief over time. Missing TOPAR scores after the first hour were imputed using the last-observation-carried-forward approach.

Secondary Outcome Measures:
  • Improvement in Pain Severity Determined by Visual Analog Scale (VAS). [ Time Frame: Each hour of the study (0, 1, 2, 3, 4). ]
    The Visual Analog Scale (VAS) assesses pain intensity. The scale is 100 mm long; the extremes of the scale are to the left, "no pain" and to the right, "worst pain I have ever felt." The VAS score is determined by measuring the distance (in mm) from the left side of the scale to the point that the patient marked. The score ranges from 0 to 100, with higher values indicating greater pain.

Enrollment: 25
Study Start Date: May 2007
Study Completion Date: August 2011
Primary Completion Date: June 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Sildenafil Citrate
A single vaginal dose of Viagra 100 mg.
Drug: Sildenafil Citrate
A single vaginal dose of sildenafil citrate 100 mg and monitored for 4 hours.
Other Name: Viagra
Placebo Comparator: Placebo
A single vaginal dose of placebo.
Drug: Placebo
A single vaginal dose of placebo and monitored for 4 hours.
Other Name: Sugar Pill

Detailed Description:
It is well established that excess prostaglandin production in primary dysmenorrhea leads to ischemia of the uterine muscle, which consequently causes pelvic pain. A large number of drugs have been studied for pain relief in dysmenorrhea patients, with non-steroid anti-inflammatory drugs (NSAIDS) being the most effective with the overall success rate of more than 75%. Sildenafil citrate (Viagra) is an inhibitor that augments the vasodilatory effects of nitric oxide by preventing the degradation of Cyclic guanosine monophosphate (cGMP) in the uterine muscle. Sildenafil is commonly used in the treatment of male erectile dysfunction, pulmonary hypertension in children and adults, and in vitro fertilization. To date it has not been used in the treatment of primary dysmenorrhea.

Ages Eligible for Study:   18 Years to 35 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Primary dysmenorrhea at current visit, with a visual analogue scale (VAS) score of >35; pain defined as moderate or severe on a categorical of none, mild, moderate, severe.

Exclusion Criteria:

  • Secondary dysmenorrhea
  • Any current medication
  • Serious medical condition
  Contacts and Locations
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Please refer to this study by its identifier: NCT00123162

Nova Gradiska General Hospital
Strossmayerova 17, Zagreb, Croatia
Sponsors and Collaborators
Milton S. Hershey Medical Center
National Institutes of Health (NIH)
Principal Investigator: Richard Legro, M.D. Penn State University College of Medicine
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Richard S. Legro, M.D., Professor, Obstetrics and Gynecology and Public Health Sciences, Milton S. Hershey Medical Center Identifier: NCT00123162     History of Changes
Other Study ID Numbers: 20477
Study First Received: July 20, 2005
Results First Received: January 16, 2015
Last Updated: November 18, 2015

Keywords provided by Milton S. Hershey Medical Center:

Additional relevant MeSH terms:
Menstruation Disturbances
Pathologic Processes
Pelvic Pain
Neurologic Manifestations
Signs and Symptoms
Sildenafil Citrate
Citric Acid
Vasodilator Agents
Phosphodiesterase 5 Inhibitors
Phosphodiesterase Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Urological Agents
Calcium Chelating Agents
Chelating Agents
Sequestering Agents processed this record on May 25, 2017