Authors: Maria Onusko, Olivia Caron, Marcia Thacher, Carriedelle Fusco, and Nabarun Dasgupta
Background: Buprenorphine is a life-saving treatment for opioid use disorders (OUD) often co-formulated in a sublingual product with the opioid antagonist naloxone as a diversion prevention measure. While pharmacokinetic studies suggest the amount of naloxone absorbed with proper sublingual administration is negligible, some studies have observed more interpatient variability.1,2,3 Patients can report adverse effects of the combination, buprenorphine-naloxone product, such as headache, nausea, vomiting, dyspepsia, diaphoresis, and fatigue.4 This study sought to assess the levels of naloxone detected in confirmatory urine drug screens (UDS), interpatient variability of naloxone absorption, and any patient specific characteristics (labs, comorbidities, concurrent medications) that may impact absorption of naloxone sublingually. Chart reviews were also conducted to identify any withdrawal symptoms reported at the time of the drug screen. This study was conducted at the Mountain Area Health Education Center (MAHEC), a federally qualified health center in Asheville, NC. The OBOT clinic is a part of one of MAHEC’s outpatient family medicine clinics.
Methods: As a qualitative improvement project, the research team requested a registry for all patients on buprenorphine-naloxone products between 5/1/2023 and 9/1/2024. Data points extracted from EHR include patient name, patient identification number, date of birth, age, height in inches, weight in kilograms, primary insurance carrier, concomitant benzodiazepine prescribed, type of buprenorphine-naloxone product, strength of product, duration of medication for OUD treatment at Mountain Area Health Education Center’s OBOT program, serum creatinine, LFTs, and date of last BMP. Two PharmD students manually extracted the following data points between 7/1/24 and 9/30/24: dosing instructions, total daily buprenorphine dose, total daily naloxone dose, quantities of buprenorphine, norbuprenorphine, and naloxone present on UDS, any other positive results on UDS, date of last confirmatory urine drug screen, any withdrawal symptoms reported at time of UDS, and other pertinent comorbidities (Hepatitis C, NASH, cirrhosis). Due to the high number of patients with reported naloxone, this project was expanded to a research analysis. IRB #2402187 submitted in March 2025 and granted exemption. Data will be analyzed by a research scientist. Results will be reviewed and themes identified by the research team.
Results
In progress
Conclusions:
In progress
References:
- Heidbreder C, Fudala PJ, Greenwald MK. History of the discovery, development, and FDA-approval of buprenorphine medications for the treatment of opioid use disorder. Drug and Alcohol Dependence Reports. 2023;6:100133. doi:10.1016/j.dadr.2023.100133
- Strickl DM, Burson JK. Sublingual Absorption of Naloxone in a Large Clinical Population. Journal of Drug Metabolism & Toxicology. 2018;9(4):1-4. Accessed March 31, 2026. https://www.longdom.org/open-access/sublingual-absorption-of-naloxone-in-a-large-clinical-population-25281.html
- Michel I, Ochal D, Paharia A, Jannetto P, Breitinger S, Oesterle T. Absorption of naloxone in patients prescribed buprenorphine‐naloxone. The American Journal on Addictions. Published online February 2, 2025. doi:https://doi.org/10.1111/ajad.13674
- Providers Clinical Support System Medications for Opioid Use Disorders Buprenorphine Prescribing Flexibility: Buprenorphine Prescribing Flexibility: Buprenorphine Monoproduct for Adverse Effects Buprenorphine Monoproduct for Adverse Effects from Buprenorphine/Naloxone from Buprenorphine/Naloxone. https://pcssnow.org/wp-content/uploads/2024/03/Buprenorphine-Prescribing-Flexibility.pdf
