Recent evidence suggests that opioid therapy may cause a biphasic response, i.e. initial pain relief followed paradoxically by a longer lasting hypersensitivity to pain. Recent genetic analysis in mice suggests that beta adrenergic receptor antagonists reduce opiate-induced hyperalgesia (OIH). The purpose of this study is to determine the analgesic and antihyperalgesic properties of the beta-blocker propranolol on remifentanil-induced hypersensitivity in humans.
The investigators want to determine the analgesic and antihyperalgesic properties of the beta-blocker propranolol on remifentanil-induced hypersensitivity in humans. The investigators hope to learn whether the administration of beta-blocker propranolol will significantly diminish the hyperalgesic response after administration of an opioid.
The primary outcome measure for this study is change in size (area) of secondary hyperalgesia after cessation of remifentanil infusion, a measure of OIH.
