Individuals who are on long-term opioid therapy (LTOT) for chronic noncancer pain are frequently admitted to the hospital with acute pain, exacerbations of chronic pain, or comorbidities. Consequently, hospitalists find themselves faced with complex treatment decisions in the context of uncertainty about the effectiveness of LTOT as well as concerns about risks of overdose, opioid use disorders, and adverse events. Our multidisciplinary team sought to synthesize guideline recommendations and primary literature relevant to assessing medical inpatients on LTOT, with the objective of assisting practitioners in balancing effective pain treatment and opioid risk reduction. We identified no primary studies or guidelines specific to assessing medical inpatients on LTOT. Recommendations from outpatient guidelines on LTOT and guidelines on pain management in acute-care settings include the following: evaluate both pain and functional status, differentiate acute from chronic pain, investigate the preadmission course of opioid therapy, obtain a psychosocial history, screen for mental health conditions, screen for substance use disorders, check state prescription drug monitoring databases, order urine drug immunoassays, detect use of sedative-hypnotics, and identify medical conditions associated with increased risk of overdose and adverse events. Although approaches to assessing medical inpatients on LTOT can be extrapolated from related guidelines, observational studies, and small studies in surgical populations, more work is needed to address these critical topics for inpatients on LTOT.