Tolerability of concomitant use of selective serotonin reuptake inhibitors or serotonin-norepinephrine reuptake inhibitors and oxymorphone extended release.

BACKGROUND: Opioids and antidepressants are frequently prescribed for chronic low back pain (cLBP). This post hoc analysis was conducted to assess the tolerability of oxymorphone extended release (ER) for cLBP in patients taking selective serotonin reuptake inhibitors (SSRIs) or serotonin-norepinephrine reuptake inhibitors (SNRIs) compared with patients not taking SSRIs/SNRIs.

METHODS: Patients in 2 clinical trials (NCT00225797, November 22, 2004 to July 18, 2005; NCT00226421, October 13, 2004 to August 19, 2005) aged ≥ 18 years with moderate to severe cLBP were titrated to a stabilized dose of oxymorphone ER during an open-label titration phase and then randomized to treatment with this dose or placebo every 12 hours for 12 weeks. In a post hoc analysis, adverse events (AEs) were compared between patients taking versus not taking SSRIs/SNRIs. Treatment efficacy was assessed as change from baseline in average daily pain intensity on a 100-mm visual analog scale.

RESULTS: Of 575 patients enrolled, 45 of 89 (50.6%) taking SSRIs/SNRIs and 303 of 486 (62.3%) not taking SSRIs/SNRIs successfully titrated to oxymorphone ER. The frequency of any AE did not differ significantly between the 2 subpopulations. During the titration phase, serious AEs occurred more frequently in patients taking SSRIs/SNRIs (3/89; 3.4%) compared with those not taking SSRIs/SNRIs (4/486; 0.8%; P = 0.04); however, during the double-blind treatment phase, there was no significant difference in the frequency of serious AEs in patients treated with oxymorphone ER taking (1/29; 3.4%) versus those not taking (3/146; 2.0%) SSRIs/SNRIs. Visual analog scale scores were similar in patients taking versus those not taking SSRIs/SNRIs throughout the study.

CONCLUSION: The concomitant use of oxymorphone ER with SSRIs or SNRIs was well tolerated in patients with cLBP.