Viagra in the Treatment of Primary Dysmenorrhea

Study Overview
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Brief Summary
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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.

Detailed Description
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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.

Official Title
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Sildenafil Citrate in the Treatment of Primary Dysmenorrhea

Conditions
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Dysmenorrhea

Intervention / Treatment
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* Drug: Sildenafil Citrate
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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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

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Sildenafil Citrate<br>A single vaginal dose of Viagra 100 mg. | Drug: Sildenafil Citrate<br>* A single vaginal dose of sildenafil citrate 100 mg and monitored for 4 hours.<br>* Other names: Viagra;|
| Placebo Comparator: Placebo<br>A single vaginal dose of placebo. | Drug: Placebo<br>* A single vaginal dose of placebo and monitored for 4 hours.<br>* Other names: Sugar Pill;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 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. | 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. | Hours 1, 2, 3 and 4. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Improvement in Pain Severity Determined by Visual Analog Scale (VAS). | 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. | Each hour of the study (0, 1, 2, 3, 4). | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Sildenafil