A Phase 2 interventional study of oral cannabinoid and oral codeine/acetaminophen in Photorefractive Keratectomy, Myopia and Hyperopia, sponsored by University of Florida. Completed at 1 site in United States. Open to participants aged 18 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-08-07.
Sponsored by University of Florida · Phase 2, Interventional, and Treatment
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.
1,159 studies on the registry are indexed under Myopia; 225 are open to participants now.
This study's enrollment of 35 is below the median of 78 across 923 interventional studies indexed under Myopia.
Browse Myopia studies →University of Florida is the lead sponsor of 1,287 studies on the registry; 199 are open to participants now.
Of its 180 completed or terminated interventional studies of FDA-regulated products, 143 (79%) have results posted.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Oral cannabinoid
Drug: oral cannabinoid
Oral codeine-acetaminophen for controlling pain
Combination Product: oral codeine/acetaminophen
dronabinol
Also known as: dronabinol
Drug pages: Codeine · Acetaminophen
10 tablets of acetaminophen-codeine combination (300-30mg) without refills.
Pain as Recorded by the FACES Scale (Maximum) After First Surgery
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"
Time frame: 1 week after first surgery
Pain as Recorded by the FACES Scale (Maximum) After Second Surgery
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"
Time frame: 1 week after second surgery
Uncorrected Visual Acuity of First Eye Surgery
Uncorrected visual acuity as measured by Snellen Chart
Time frame: 3 months after first surgery
PROWL-SS
An online questionnaire derived from the Patient-Reported Outcomes With LASIK (PROWL) will be given to patients after PRK at 3 months. It ranges from 0-100, where 100 indicates best possible vision and satisfaction, while 0 indicates worst possible vision and satisfaction.
Time frame: 3 month
Quality of Life Refractive Correction Survey
The QIRC measures quality of life associated with vision and eyewear problems, measured at 3 months. It ranges from 0-100, where 0 indicates best possible vision and quality of life and 100 indicates worst possible vision and quality of life.
Time frame: 3 months
Ocular Discomfort Questionnaire
An online questionnaire derived from the Ocular Surface Disease Index (OSDI) at 3 months. It ranges from 0-48, where 0 indicates no eye discomfort and 48 indicates constant, debilitating, worst-possible eye discomfort or pain.
Time frame: 3 months
Uncorrected Visual Acuity of Second Eye Surgery
Uncorrected visual acuity as measured by Snellen Chart
Time frame: 3 months after second surgery
Thirty-five myopic patients were recruited and had surgery for both eyes completed between 1/1/2024 and 12/31/2024. Patients seeking refractive surgery and who were candidates for photorefractive keratectomy were approached with the option to enroll in the ophthalmology clinic.
| Milestone | Group 1 | Group 2 |
|---|---|---|
| Started | 16 | 19 |
| Completed | 16 | 19 |
| Not completed | 0 | 0 |
| Milestone | Group 1 | Group 2 |
|---|---|---|
| Started | 16 | 19 |
| Completed | 16 | 19 |
| Not completed | 0 | 0 |
| Milestone | Group 1 | Group 2 |
|---|---|---|
| Started | 16 | 19 |
| Completed | 16 | 19 |
| Not completed | 0 | 0 |
| Milestone | Group 1 | Group 2 |
|---|---|---|
| Started | 16 | 19 |
| Completed | 16 | 19 |
| Not completed | 0 | 0 |
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"
| units on a scale | Cannabidiol | Tylenol T3 |
|---|---|---|
| Pain as Recorded by the FACES Scale (Maximum) After First Surgery | 1.33 ± 0.95 | 1.27 ± 0.89 |
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"
| units on a scale | Cannabidiol | Tylenol T3 |
|---|---|---|
| Pain as Recorded by the FACES Scale (Maximum) After Second Surgery | 1.46 ± 0.82 | 1.79 ± 1.12 |
Uncorrected visual acuity as measured by Snellen Chart
| LogMAR | Cannabidiol | Tylenol T3 |
|---|---|---|
| Uncorrected Visual Acuity of First Eye Surgery | -0.123 ± 0.119 | -0.054 ± 0.169 |
An online questionnaire derived from the Patient-Reported Outcomes With LASIK (PROWL) will be given to patients after PRK at 3 months. It ranges from 0-100, where 100 indicates best possible vision and satisfaction, while 0 indicates worst possible vision and satisfaction.
| score on a scale | Group 1 | Group 2 |
|---|---|---|
| Pre-op | 58.0 ± 20.1 | 60.9 ± 18.3 |
| Post-op Month 3 | 81.6 ± 9.0 | 85.6 ± 6.9 |
The QIRC measures quality of life associated with vision and eyewear problems, measured at 3 months. It ranges from 0-100, where 0 indicates best possible vision and quality of life and 100 indicates worst possible vision and quality of life.
| score on a scale | Group 1 | Group 2 |
|---|---|---|
| Pre-op | 37.7 ± 6.2 | 37.6 ± 10.6 |
| Post-op Month 3 | 19.2 ± 6.0 | 26.4 ± 6.3 |
An online questionnaire derived from the Ocular Surface Disease Index (OSDI) at 3 months. It ranges from 0-48, where 0 indicates no eye discomfort and 48 indicates constant, debilitating, worst-possible eye discomfort or pain.
| score on a scale | Group 1 | Group 2 |
|---|---|---|
| Pre-op | 4.9 ± 5.7 | 4.8 ± 5.4 |
| Post-op Month 3 | 4.9 ± 4.8 | 3.9 ± 4.0 |
Uncorrected visual acuity as measured by Snellen Chart
| LogMAR | Cannabidiol | Tylenol T3 |
|---|---|---|
| Uncorrected Visual Acuity of Second Eye Surgery | -0.051 ± 0.16 | -0.075 ± 0.121 |
Collected over 3 months. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Cannabidiol | 0/35 (0%) | 0/35 (0%) | 0/35 (0%) |
| Tylenol T3 | 0/35 (0%) | 0/35 (0%) | 0/35 (0%) |
| Age, Continuous(Years) | Group 1 | Group 2 | Total |
|---|---|---|---|
| Mean | 34.2 ± 5.2 | 30.6 ± 6.8 | 32.5 ± 6.3 |
| Sex: Female, Male(Participants) | Group 1 | Group 2 | Total |
|---|---|---|---|
| Female | 9 | 10 | 19 |
| Male | 7 | 9 | 16 |
| Race (NIH/OMB)(Participants) | Group 1 | Group 2 | Total |
|---|---|---|---|
| American Indian or Alaska Native | 0 | 0 | 0 |
| Asian | 0 | 0 | 0 |
| Native Hawaiian or Other Pacific Islander | 0 | 0 | 0 |
| Black or African American | 0 | 0 | 0 |
| White | 0 | 0 | 0 |
| More than one race | 0 | 0 | 0 |
| Unknown or Not Reported | 16 | 19 | 35 |
| Visual Acuity(LogMAR) | Group 1 | Group 2 | Total |
|---|---|---|---|
| without glasses or contacts | 1.109 ± 0.452 | 1.290 ± 0.475 | 1.207 ± 0.470 |
| With glasses or contacts | -0.062 ± 0.085 | 0.026 ± 0.338 | -0.014 ± 0.257 |
PDFs hosted by the registry, ClinicalTrials.gov.
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Studies of the drug tested here: Cannabinoids