Effectiveness of Duloxetine on Oxaliplatin-induced Allodynia and Hyperalgesia in Rats

Development of painful oxaliplatin-induced peripheral neuropathy (OIPN) is a major problem in people who receive oxaliplatin as part of cancer treatment. The pain experienced by those with OIPN can be seriously debilitating and lead to discontinuation of an otherwise successful treatment. Duloxetine is currently the only recommended treatment for established painful OIPN recommended by the American Society of Clinical Oncology, but its preventative ability is still not clear. This study examined the ability of duloxetine to prevent signs of chronic OIPN in female (n = 12) and male (n = 21) rats treated with the chemotherapeutic agent oxaliplatin. Using an established model of OIPN, rats were started on duloxetine (15 mg) one week prior to oxaliplatin administration and continued duloxetine for 32 days. Behavioral testing for mechanical allodynia and mechanical hyperalgesia was done with selected von Frey filaments. Significant posttreatment differences were found for allodynia in female (p = .004), but not male rats. Duloxetine was associated with significant differences for hyperalgesia in both female (p < .001) and male (p < .001) rats. These findings provide preliminary evidence of the preventative effects of duloxetine on both oxaliplatin-induced allodynia and hyperalgesia in male and female rats, with a difference noted in response between the sexes.