OBJECTIVE: To identify possible underlying causes of poor oral opioid effectiveness. METHODS: Ninety-five (95) adults who were referred for evaluation and medical management of their intractable @entity158 were screened to determine if oral opioids provided enough @entity158 relief to physically and mentally function and carry out activities of daily living. A clinical evaluation included history, physical examination, @entity12325 enzyme testing and a @entity10748 injection to help confirm lack of oral opioid effectiveness. RESULTS: Twenty (20; 21.1%) of the 95 @entity1 reported that three or more oral opioids had not provided enough @entity158 relief to allow them to mentally and physically function and carry out activities of daily living. @entity1 all reported some typical symptoms of @entity8884 including @entity390 and @entity6123 , and 14 (70.0%) reported that they had observed undigested medication in their stools. Fifteen (15; 75.0%) had experienced @entity158 relief with an injectable opioid. Two major causes for lack of oral opioid effectiveness were apparent: (1) @entity344 (11; 55.0%) and (2) @entity12325 enzymatic defects (9; 45.0%). In addition to these basic causes, a number of other possible contributing factors were identified which included abdominal, pelvic and spine surgeries, traumatic brain and @entity9389 , and @entity792 . CONCLUSIONS: There is a group of intractable @entity158 @entity1 who do not effectively metabolize oral opioids. Although @entity344 and @entity12325 enzymatic defects appeared to be dominant causes of oral opioid ineffectiveness, there were other possible contributing factors such as abdominal, pelvic and spine surgeries, @entity135 , and @entity792 . @entity158 @entity1 who report poor oral opioid effectiveness should be evaluated for the presence of underlying pathologic conditions which may interfere with oral opioid metabolism and, if found, be considered for nonoral opioid treatment.

Why oral opioids may not be effective in a subset of chronic pain XXXX .

@entity1 :: ('9606', 'Species') :: ['Patients', 'patients'] @entity135 :: ('MESH:D006258', 'Disease') :: ['head and neck trauma'] @entity12325 :: ('4051', 'Gene') :: ['cytochrome P450'] @entity390 :: ('MESH:D009325', 'Disease') :: ['nausea'] @entity8884 :: ('MESH:D008286', 'Disease') :: ['malabsorption'] @entity9389 :: ('MESH:D019838', 'Disease') :: ['neck injury'] @entity6123 :: ('MESH:D045602', 'Disease') :: ['steatorrhea'] @entity344 :: ('MESH:D005767', 'Disease') :: ['gastrointestinal disease', 'gastrointestinal disorder'] @entity792 :: ('MESH:D001327', 'Disease') :: ['autoimmune disease', 'autoimmune disorders'] @entity158 :: ('MESH:D010146', 'Disease') :: ['Pain', 'pain'] @entity10748 :: ('MESH:D004091', 'Chemical') :: ['hydromorphone']
@entity1 :: (9606,Species) :: ['patients']
