Oral Gabapentin Versus Placebo for Treatment of Postoperative Pain Following Photorefractive Keratectomy

Study Overview
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Brief Summary
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The purpose of this study is to determine the effectiveness of an oral medication called gabapentin in reducing pain after Photorefractive Keratectomy (PRK) eye surgery and to assess the frequency of use of rescue medication interventions, defined as non-steroidal anti-inflammatory (NSAID) eye drops and oral narcotic medication.

Official Title
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Oral Gabapentin Versus Placebo for Treatment of Postoperative Pain Following Photorefractive Keratectomy: A Randomized, Double-masked, Single Center, Placebo-controlled Clinical Trial

Conditions
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Postoperative Pain

Intervention / Treatment
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* Drug: Gabapentin
* Drug: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ability to understand and provide informed consent to participate in this study and complete follow-up visits. Planned Photorefractive keratectomy (PRK) at the WRAMC Center for Refractive Surgery. Male or female, of any race, and at least 21 years old at the time of the pre-operative examination, and have signed an informed consent. The lower age limit of 21 years is intended to ensure documentation of refractive stability. Access to transportation to meet follow-up requirements. Exclusion Criteria: Any reason to be excluded for PRK. Female subjects who are pregnant, breast feeding or intend to become pregnant during the study. Female subjects will be given a urine pregnancy test prior to participating in the study to rule out pregnancy. [Pregnancy and breastfeeding are contraindications to refractive surgery in general, including PRK, whether participating in this study or not]. Patients with known allergy, sensitivity or inappropriate responsiveness to Gabapentin or any of the medications used in the post-operative course. Patients with known depressed renal function. Any physical or mental impairment that would preclude participation in any of the examinations.

Ages Eligible for Study
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Minimum Age: 21 Years

Sexes Eligible for Study
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All

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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Gabapentin<br>oral medication | Drug: Gabapentin<br>* Gabapentin 300 mg taken by mouth thrice daily for 7 days<br>|
| Placebo Comparator: placebo<br> | Drug: placebo<br>* placebo (sugar pill) taken by mouth thrice daily for 7 days<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Level of Pain | level of pain was measured using the Visual Analog Scale (VAS)ranging from 0 (none) to 10 (worst possible pain) | 2 hours postoperatively | 
| Level of Pain | level of pain was measured using the Visual Analog Scale (VAS)ranging from 0 (none) to 10 (worst possible pain) | day 1 postoperatively | 
| Level of Pain | level of pain was measured using the Visual Analog Scale (VAS)ranging from 0 (none) to 10 (worst possible pain) | 3 days postoperatively | 
| Level of Pain | level of pain was measured using the Visual Analog Scale (VAS)ranging from 0 (none) to 10 (worst possible pain) | 4 days postoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurence of Use of Rescue Medication | Occurrence of use of either ketorolac eyedrops(Acular) or oxycodone-acetaminophen tablet (Percocet), or both was measured | 2 hours to 4 days postoperatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Gabapentin, PRK, pain