Comparison of Oral Gabapentin and Pregabalin in Postoperative Pain Control After Photorefractive Keratectomy
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ClinicalTrials.gov Identifier: NCT00954187 |
Recruitment Status :
Terminated
(PI left institution)
First Posted : August 7, 2009
Results First Posted : September 25, 2014
Last Update Posted : January 9, 2017
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Purpose: To compare the efficacy of oral gabapentin and its newer analogue pregabalin in postoperative pain control after photorefractive keratectomy (PRK).
Methods: One hundred and four patients who meet the inclusion criteria undergoing PRK in one or both eyes will be randomized into one of two treatment groups. Those in group A will be treated with gabapentin, and those in group B will be treated with pregabalin to control postoperative PRK pain. Patients in both groups will begin treatment two hours prior to surgery in order to achieve therapeutic blood levels of each medication. After surgery the patients will assess their pain level using the visual analogue scale (VAS) at different intervals of time - one hour after surgery, the evening of the surgery, and three times each day for three subsequent days. Patients will also daily assess their level of somnolence using the Epworth Sleepiness Scale (ESS) and record the presence of dizziness for the same amount of time. On the fourth day they will return to clinic for a postoperative appointment. At that time the pain, sleepiness, and dizziness assessment scales will be collected and analyzed. The patients will return one month later to further assess long-term pain and healing after PRK.
Results: Both gabapentin and pregabalin have been shown in previous studies to treat postoperative pain effectively. The effects of gabapentin 300 mg TID for 3 days versus pregabalin 50 mg TID for 3 days on decreasing overall postoperative pain following PRK will be presented.
Conclusion: The effectiveness of the two different treatment medications will be analyzed, and the conclusion will be based on the results.
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Postoperative Pain | Drug: Gabapentin Drug: pregabalin | Not Applicable |
METHODS:
One hundred and four patients who meet the inclusion criteria undergoing photorefractive keratectomy (PRK) in one or both eyes will be randomly assigned into one of two treatment groups via computer. Those in group A will be treated with gabapentin and those in group B will be treated with pregabalin to control postoperative PRK pain. Patients in both groups will begin treatment two hours prior to surgery. Patients in the gabapentin group will take 300 mg three times a day starting two hours prior to surgery and will continue for a total of four days. Patients in the pregabalin group will take 50 mg three times a day starting two hours prior to surgery and will also continue for four days.
Only the refractive surgery coordinator and the patient will know what medication the patient is taking. The patient will be instructed not to share this information with any other study participants or their surgeon. The coordinator will keep a list of the patients ID numbers and the treatments they are receiving.
Prior to surgery, each patient will be taught how to assess their pain level using the visual analogue scale (VAS), a well documented method of pain assessment. After surgery the patients will assess their pain levels at different intervals of time - one hour after surgery, the evening of the surgery, and three times a day for four subsequent days. Patients will also daily assess their level of somnolence using the Epworth Sleepiness Scale (ESS) and record the presence of dizziness daily for the same amount of time. On the fourth day they will return to clinic for a post operative appointment. At that time the pain assessment scales will be collected and analyzed. The patients will return at one month to further assess long term pain after PRK.
Statistical Analysis:
Postoperative pain levels recorded using the visual analogue scales, ESS, and self reported dizziness assessments will be collected on the fourth postoperative day. These will be compiled into data sets and analyzed. Data will be compiled into means with lower and upper quartiles and analyzed using a two-sided t test. The difference in pain levels will be described throughout the postoperative period to determine if one medication significantly reduces postoperative pain initially within the first 24 hours, during the interval between 24 hours to four days, and further after surgery (one month postoperatively). Data regarding levels of somnolence and dizziness will also be reported.
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 8 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Double (Investigator, Outcomes Assessor) |
Primary Purpose: | Treatment |
Official Title: | Comparison of Oral Gabapentin and Pregabalin in Postoperative Pain Control After Photorefractive Keratectomy: a Prospective, Randomized Study. |
Study Start Date : | November 2009 |
Actual Primary Completion Date : | September 2012 |
Actual Study Completion Date : | April 2013 |

Arm | Intervention/treatment |
---|---|
Experimental: Gabapentin
Neurontin
|
Drug: Gabapentin
Gabapentin - 300 mg three times a day starting two hours prior to surgery and will continue for a total of four days
Other Name: Neurontin |
Experimental: Pregabalin
Lyrica
|
Drug: pregabalin
50 mg PO TID
Other Name: Lyrica |
- Decreased Overall Pain Score as Measured by the Visual Analogue Scale [ Time Frame: one month ]No data was collected or analyzed. No study procedures were performed.

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Ages Eligible for Study: | 18 Years to 70 Years (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | Yes |
Inclusion Criteria:
- 18 years of age or older
- Undergoing PRK in at least one eye
Exclusion Criteria:
- Serious medical problems within the last 6 months including myocardial infarction (heart attack), congestive heart failure, stroke, deep vein thrombosis, pulmonary embolism, and other conditions, etc.
- Serious kidney disease as evidenced by the need for dialysis or kidney transplant.
- History of seizure or other neurologic disorders.
- Patients intending to become pregnant or who are pregnant or nursing over the projected course of treatment.
- Currently taking gabapentin or pregabalin for other medical purposes.
- Known allergic reaction to gabapentin or pregabalin from previous use.
- Plans to move out of the area within 8 weeks after the surgery.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00954187
United States, California | |
Loma Linda University - Ophthalmology | |
Loma Linda, California, United States, 92354 |
Principal Investigator: | Julio Narvaez, MD | Loma Linda University |
Responsible Party: | Loma Linda University |
ClinicalTrials.gov Identifier: | NCT00954187 |
Other Study ID Numbers: |
59070 |
First Posted: | August 7, 2009 Key Record Dates |
Results First Posted: | September 25, 2014 |
Last Update Posted: | January 9, 2017 |
Last Verified: | November 2016 |
Pain, Postoperative Postoperative Complications Pathologic Processes Pain Neurologic Manifestations Pregabalin Gabapentin Analgesics Sensory System Agents Peripheral Nervous System Agents Physiological Effects of Drugs Anticonvulsants |
Calcium Channel Blockers Membrane Transport Modulators Molecular Mechanisms of Pharmacological Action Calcium-Regulating Hormones and Agents Anti-Anxiety Agents Tranquilizing Agents Central Nervous System Depressants Psychotropic Drugs Excitatory Amino Acid Antagonists Excitatory Amino Acid Agents Neurotransmitter Agents Antimanic Agents |