Variability in Analgesic Response to Ibuprofen

May 4, 2026 updated by: University of Pennsylvania

Mechanisms of Variability in the Analgesic Response to Ibuprofen Following Third Molar Extraction

Nonsteroidal anti-inflammatory drugs (NSAIDs), like ibuprofen, are recommended as first-line treatment for post-surgical dental pain. However, there is variability in analgesic response, and some patients require supplemental opioids for adequate pain relief. The goal of this study is to identify the factors that contribute to the need for opioid after third molar extraction to help limit unnecessary opioid prescriptions in patients who will have good pain relief with ibuprofen alone.

Study Overview

Detailed Description

The dramatic increase in opioid prescriptions over the past years has been linked to the concomitant rise in opioid addiction and to deaths from opioid abuse. Young adults' initial exposure to opioid analgesics is often following extraction of their impacted third molars, with an average of 5,000,000 cases in the USA per year. Over-prescribing of opioids for surgical pain, often 2-5 times more than patients actually use, further exacerbates this problem, as patients tend to save leftover pills rather than discard them. Up to 70% of individuals who become addicted to prescription opioids had access to leftover pills prescribed for others. This is particularly troubling as the odds of transitioning to heroin from prescription opioid abuse are much higher than other suspected gateway drugs, about 40 fold greater than non-gateway drug users.

Multiple studies have demonstrated that non-addicting nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and diclofenac are effective in relieving pain after dental impaction surgery, being at least equally efficacious as optimal doses of immediate release opioid formulations combined with acetaminophen. However, these assessments of pain relief represent average scores and approximately 22% and 50% of individuals required additional opioid-containing rescue analgesics when ibuprofen and diclofenac were employed at FDA-approved dosages. A deeper understanding of the sources of variability in pain relief should allow improvements in the overall efficacy of NSAIDs by targeting treatment to those who are most likely to receive sufficient pain relief. Thus, optimizing pain therapy with NSAIDs by personalization would be expected to help limit the unnecessary prescription of highly addicting immediate release opioids. Moreover, these results may have applicability to other types of pain that are driven by inflammation.

Study Type

Observational

Enrollment (Estimated)

200

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

    • Pennsylvania
      • Philadelphia, Pennsylvania, United States, 19104
        • Recruiting
        • University of Pennsylvania School of Dental Medicine
        • Contact:
        • Principal Investigator:
          • Katherine N Theken, PharmD, PhD
        • Sub-Investigator:
          • Elliot V Hersh, DMD, MS, PhD
        • Sub-Investigator:
          • Neeraj Panchal, DDS, MA, MD

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

Yes

Sampling Method

Probability Sample

Study Population

Patients presenting for surgical extraction of partial or full bony impacted mandibular third molars at the Oral Surgery Clinics at Penn Dental Medicine

Description

Inclusion Criteria:

  1. Provision of signed and dated informed consent form
  2. Stated willingness to comply with all study procedures and availability for the duration of the study
  3. Ability to take oral medication and be willing to adhere to the study treatment regimen
  4. Men and women greater than 18 years of age requiring extraction of at least one impacted mandibular third molar tooth (at least 50% covered with bone).
  5. Absence of other major medical problems or contraindications to surgery or study drugs.
  6. Female subjects of child bearing potential must be using a medically acceptable method of contraception (oral contraception, Depo-Provera injection, IUD, condom with spermicide, diaphragm, cervical cap, progestin implant, abstinence, tubal ligation, oophorectomy, TAH) throughout the entire study period. All female subjects must consent to a urine pregnancy test at screening and a urine pregnancy test on the day of surgery, which must be negative at all time points.
  7. Has not ingested caffeine-containing products within 12 hours of surgery.
  8. All subjects must consent to a urine drug test at screening. Results must be negative (except for THC) unless the subject is on a stable dose of a non-analgesic drug for a legitimate medical purpose. A positive test for THC will be permitted and the frequency of use will be documented. A positive result will be reported to the subject.
  9. Does not consume more than 1 alcoholic beverage per day on average.
  10. Subjects must reach a level of at least moderate pain within four hours of surgery completion, with a pain score greater than or equal to 4 on a 0-10 numerical pain scale
  11. Subjects must be willing and able to complete safety and efficacy diaries.
  12. An escort must be available to pick up the subject at the end of at the end of the surgical/dosing visit (Visit #2).

Exclusion Criteria:

  1. Female subjects who are pregnant or nursing a child.
  2. Subjects who have received an investigational drug or used an experimental medical device within 30 days prior to screening, or who gave a blood donation of ≥ one pint within 8 weeks prior to screening.
  3. Subjects who are sensitive or allergic to ibuprofen, acetaminophen, or their components.
  4. Subjects who are sensitive or allergic to aspirin or other NSAIDs.
  5. Subjects who are sensitive or allergic to oxycodone or other opioids (excluding nausea and constipation).
  6. Presence of a serious medical condition (e.g. poorly controlled hypertension or diabetes, gastrointestinal disorders such as bleeding ulcer, coagulation or bleeding disorders, significantly impaired cardiac, renal, hepatic, respiratory, or thyroid function) that according to the investigator may interfere with interpretation of the study results or compromise the safety of a potential subject.
  7. Acute local infection at the time of surgery that could confound post-surgical evaluation.
  8. Use of any confounding prescription or non-prescription drug within 24 hours of the surgical procedure, including analgesics, sedating antihistamine, sedative, alcohol, or CNS/psychotropic agents (i.e. sleep aids, benzodiazepines). Hormonal contraceptives, hormone replacement therapy (including males taking testosterone as a hormone replacement to treat a documented low testosterone level), or thyroid replacement hormones are allowed. Individuals taking other/additional chronic stable medications can be considered on a case-by-case basis for inclusion in the study if agreed upon by judgment of the investigator.
  9. Subjects with any abnormal laboratory value or physical finding that according to the investigator may interfere with interpretation of the study results, be indicative of an underlying disease state, or compromise the safety of a potential subject.
  10. Subjects who have a history of opioid use disorder or other substance use disorder, based upon history and judgment of the Investigator.
  11. Subjects who are unwilling to provide a blood sample for genetic analyses.
  12. Employees of the principal investigator, sub-investigators, or relative of an employee who is directly involved in this study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Complete Responders
Patients who do not require supplemental opioids, in addition to a standard-of-care NSAID-based pain management regimen, for pain relief following third molar extraction
Partial Responders
Patients who require supplemental opioids (oxycodone 5 mg), in addition to a standard-of-care NSAID-based pain management regimen, for pain relief following third molar extraction

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Supplemental Opioid Use
Time Frame: Up to 7 days after third molar extraction
Use of oxycodone in addition to ibuprofen + acetaminophen
Up to 7 days after third molar extraction

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
DNA sequencing
Time Frame: 1 day
Assessment of genetic variation
1 day
Gene Expression Profiling
Time Frame: Up to 7 days after third molar extraction
mRNA levels will be measured in peripheral blood mononuclear cells
Up to 7 days after third molar extraction
COX-1 activity
Time Frame: Up to 7 days after third molar extraction
COX-1 activity will be measured ex vivo using a whole blood assay and in vivo by quantifying concentrations of prostaglandin metabolites in urine.
Up to 7 days after third molar extraction
COX-2 activity
Time Frame: Up to 7 days after third molar extraction
COX-2 activity will be measured ex vivo using a whole blood assay and in vivo by quantifying concentrations of prostaglandin metabolites in urine.
Up to 7 days after third molar extraction
Pain intensity score
Time Frame: Up to 7 days after third molar extraction
Rating of pain from 0 (no pain) to 10 (worst imaginable pain)
Up to 7 days after third molar extraction
Inflammatory mediator profiling
Time Frame: Up to 7 days after third molar extraction
Assessment of cytokines in plasma
Up to 7 days after third molar extraction
Complete blood count with differential
Time Frame: Up to 7 days after third molar extraction
Assessment of proportions of red blood cells, white blood cells, and platelets in whole blood
Up to 7 days after third molar extraction

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Katherine N Theken, PharmD, PhD, University of Pennsylvania

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

January 3, 2025

Primary Completion (Estimated)

September 1, 2027

Study Completion (Estimated)

September 1, 2027

Study Registration Dates

First Submitted

August 1, 2024

First Submitted That Met QC Criteria

August 1, 2024

First Posted (Actual)

August 6, 2024

Study Record Updates

Last Update Posted (Actual)

May 6, 2026

Last Update Submitted That Met QC Criteria

May 4, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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