title: Likeability and abuse liability of commonly prescribed opioids.
abstract: BACKGROUND
  Nonmedical use of prescription opioid analgesics is associated with epidemic levels of morbidity and mortality. There are several factors that affect the abuse liability of the various opioids, including likability or the pleasurable subjective effects. Due to rising public health concerns over escalating prescription opioid abuse, we sought to examine the literature about abuse liability with a specific focus on likability studies.
  
  
  METHODS
  A search of EMBASE and MEDLINE databases identified articles that described the comparative likeability and/or abuse potential of hydrocodone and oxycodone relative to each other and/or of either one to morphine. After an assessment of study quality using the Oxford/Jadad scale, relevant details such as demographics, study design, and outcome measures were compiled into an evidence table.
  
  
  RESULTS
  We identified nine studies that met inclusion criteria. All were double-blinded, randomized, placebo-controlled crossover studies and scored 5 out of 5 Jadad scale. There was no consistent clinically significant difference between abuse liability of morphine and hydrocodone. Oxycodone demonstrated high abuse liability on the basis of its high likability scores and a relative lack of negative subjective effects.
  
  
  CONCLUSIONS
  Oral oxycodone has an elevated abuse liability profile compared to oral morphine and hydrocodone.
authors.affiliation: Department of Emergency Medicine, New York University School of Medicine, 455 First Avenue, Room 123, New York, NY 10016, USA. rachel.wightman@nyumc.org
authors.forename: Rachel
authors.initials: R
authors.lastname: Wightman
authors.forename: Jeanmarie
authors.initials: J
authors.lastname: Perrone
authors.forename: Ian
authors.initials: I
authors.lastname: Portelli
authors.forename: Lewis
authors.initials: L
authors.lastname: Nelson
mesh_terms: D000701:Analgesics, Opioid / Q000009:adverse effects*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D006853:Hydrocodone / Q000009:adverse effects*; D009020:Morphine / Q000009:adverse effects*; D009293:Opioid-Related Disorders / Q000453:epidemiology*; D010098:Oxycodone / Q000009:adverse effects*; D016032:Randomized Controlled Trials as Topic
chemical_list: D000701:Analgesics, Opioid; D006853:Hydrocodone; D009020:Morphine; D010098:Oxycodone