Effects of Tapentadol Versus Oxycodone After Hysterectomy.

Opioids remain the first-line drugs for the treatment of moderate to severe postoperative pain, but the use is limited by well-known side-effects, most of which are dose-dependent. The opioid oxycodone is standard therapeutic treatment for acute postoperative pain, either in immediate-release formulation, OxyNorm®, or as extended-release formulation, OxyContin®. Oxycodone provides analgesic effects through µ-opioid receptors in the central nervous system. Tapentadol hydrochloride/depot (Palexia/depot®) is a novel, centrally acting, strong analgesic with a dual mechanism of action on µ-opioid receptors and noradrenaline reuptake in the central nervous system. Tapentadol is an active compound, devoid of active metabolites and not reliant on enzyme systems. For these reasons, it has a low drug interaction potential. This dual mechanism also translates clinically into less adverse effects than with pure opioid agonists like oxycodone. This is probably due to less µ-opioid receptor stimulation. Tapentadol has been shown effective in models of acute, osteoarthritic, neuropathic and cancer pain. There is now an increasing use of tapentadol in postoperative pain treatment in Norway. However, there is a lack of broad-based evidence for the use of tapentadol in the post-surgical setting. So far, to our knowledge, there are only published studies on postoperative pain treatment after orthopedic and dental surgery, but none related to deep abdominal pain. Tapentadol is shown in several studies on chronic pain patients to have comparable analgesic effects to traditional opioid pain medications like oxycodone and morphine, but with a more tolerable side-effect profile. In the postoperative setting after dental or orthopedic surgery, studies have shown less nausea and constipation. It has also been suggested a lower frequency of pruritus compared with oxycodone, but no difference in central nervous system symptoms such as sleepiness or dizziness. The most dangerous side-effect