Methadone-Induced Hypoglycemia in a Hospitalized Patient.

Methadone is used as an agent for chronic pain and management of opioid use disorder. While similar pharmacologically to other opioids, methadone does have unique characteristics, including long half-life, low cost, and high oral bioavailability. While advantageous in some ways, methadone is associated with unique adverse effects not seen with other opioids (ie, hypoglycemia). In this case, we describe a patient in his late-60s with opioid use disorder on chronic methadone who presents with symptoms of generalized weakness, fatigue, and decreased appetite for 2 days. The hospital course was complicated by hypoglycemia, without obvious cause other than methadone-induced hypoglycemia. The patient was managed with supportive care to maintain normoglycemia. He was continued on methadone and instructed to follow-up with his opioid treatment program to assess for dose de-escalation to minimize future hypoglycemia risk. While other case reports of methadone-induced hypoglycemia highlight the risk of this adverse effect, our case highlights the importance of assessing methadone as a cause of hypoglycemia and provides discussion around the legality of dose de-escalation at discharge from an acute care setting.

Pharmacogenomics in Pain Management: A Review of Relevant Gene-Drug Associations and Clinical Considerations.

OBJECTIVE: To provide an overview of clinical recommendations regarding genomic medicine relating to pain management and opioid use disorder. DATA SOURCES: A literature review was conducted using the search terms pain management, pharmacogenomics, pharmacogenetics, pharmacokinetics, pharmacodynamics, and opioids on PubMed (inception to February 1, 2021), CINAHL (2016 through February 1, 2021), and EMBASE (inception through February 1, 2021). STUDY SELECTION AND DATA EXTRACTION: All relevant clinical trials, review articles, package inserts, and guidelines evaluating applicable pharmacogenotypes were considered for inclusion. DATA SYNTHESIS: More than 300 Food and Drug Administration-approved medications contain pharmacogenomic information in their labeling. Genetic variability may alter the therapeutic effects of commonly prescribed pain medications. Pharmacogenomic-guided therapy continues to gain traction in clinical practice, but a multitude of barriers to widespread pharmacogenomic implementation exist. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: Pain is notoriously difficult to treat given the need to balance safety and efficacy when selecting pharmacotherapy. Pharmacogenomic data can help optimize outcomes for patients with pain. With improved technological advances, more affordable testing, and a better understanding of genomic variants resulting in treatment disparities, pharmacogenomics continues to gain popularity. Unfortunately, despite these and other advancements, pharmacogenomic testing and implementation remain underutilized and misunderstood in clinical care, in part because of a lack of health care professionals trained in assessing and implementing test results. CONCLUSIONS: A one-size-fits-all approach to pain management is inadequate and outdated. With increasing genomic data and pharmacogenomic understanding, patient-specific genomic testing offers a comprehensive and personalized treatment alternative worthy of additional research and consideration.