Cannabinoid vs Opioid for Photorefractive Keratectomy Pain Control

Study Overview
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Brief Summary
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Photorefractive Keratectomy (PRK) is a commonly performed corneal refractive surgery but has significant post-operative pain. Pain medications after PRK are typically opioid-acetaminophen combinations. Alternatives to opioid medication are worth consideration. Patients will receive PRK in each eye sequentially, using the cannabinoid or codeine/acetaminophen for one eye and the other treatment for the fellow eye two weeks later.

Official Title
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Randomized, Controlled Cross-over Comparison of Cannabinoid to Oral Opioid for Postoperative Photorefractive Keratectomy Pain Control

Conditions
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Photorefractive Keratectomy, Myopia, Hyperopia

Intervention / Treatment
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* Drug: oral cannabinoid
* Combination Product: oral codeine/acetaminophen


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults older than 18 years with refractive stability for 1 year electing to have PRK surgery Consenting to participate Not meeting exclusion criteria will be included in the study population. Exclusion Criteria: Patients not candidates for PRK will be excluded from the study. Patients taking other pain medications for concomitant medical conditions including, but not limited to tricyclic antidepressants, gabapentin and tramadol will be excluded from the study. Additional exclusion criteria will be known or suspected allergy or hypersensitivity to any of the routine or study medications. Patients completing follow up appointments at anywhere other than UF Health Ophthalmology clinic at the Oaks will not be enrolled in the study. Patients who are pregnant or nursing are not eligible for PRK, and such patients are not eligible to enroll in this study. Female patients of child-bearing age will be pregnancy tested before surgery and study enrollment. Patients will be specifically counseled, and it will be noted in the written informed consent that use of the cannabinoid product may result in a positive THC urinalysis screening test so they may self-exclude if such a situation could cause social and/or employment conflict.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Oral cannabinoid<br>Oral cannabinoid | Drug: oral cannabinoid<br>* dronabinol<br>* Other names: dronabinol;|
| Active Comparator: Oral codeine/acetaminophen<br>Oral codeine-acetaminophen for controlling pain | Combination Product: oral codeine/acetaminophen<br>* 10 tablets of acetaminophen-codeine combination (300-30mg) without refills.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain as recorded by the FACES scale | The Wong-Baker Faces Pain Rating Scale is a pain scale that was developed by Donna Wong and Connie Baker. The scale shows a series of faces ranging from a happy face at 0, or no hurt, to a crying face at 10, which represents hurts like the worst pain imaginable | 1 week | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Uncorrected visual acuity | Uncorrected visual acuity as measured by Snellen Chart, as well as change in uncorrected visual acuity. | 1 week | 
| Subjective vision questionnaire | An online questionnaire derived from the Ocular Surface Disease Index (OSDI) and the Patient-Reported Outcomes With LASIK (PROWL) will be given to patients after PRK. A ocular discomfort score will be calculated at one week. | 1 week | 
| Corneal haze | Corneal haze will be recorded by slit lamp exam according to the Fantes scale, which measures degree of corneal haze after surface ablation. | 1 week | 
| Ocular discomfort questionnaire | An online questionnaire derived from the Ocular Surface Disease Index (OSDI) and the Patient-Reported Outcomes With LASIK (PROWL) will be given to patients after PRK. A subjective vision score will be calculated at one week. | 1 week |