Efficacy of Nalbuphine and Naloxone Administered as Nose Sprays in the Treatment of Orofacial Pain

Modeling Kappa Opioid Analgesic Mechanisms in Chronic Orofacial Pain Disorders

Patients with chronic masticatory muscle pain (i.e., pain greater than three months) or patients with burning mouth syndrome participate in this study. The aim of the study is to compare the pain killing effectiveness of nalbuphine, a narcotic pain killer, administered with either placebo or naloxone, a drug used to treat opiate overdose. A second goal is to determine if there are sex differences in these two drug regimens. Drugs will be administered with single-use intranasal spray devices. All participants will receive two sprays (one spray per nostril). One of the two sprays will be nalbuphine (5 mg). The other spray will be naloxone in half the participants and placebo in the other half.

Inclusion Criteria:

• Clinical diagnosis of temporomandibular muscle pain OR
• Clinical diagnosis of burning mouth syndrome
• Pain duration: at least 3 months
• Pain severity: 2 or greater on a 0 - 10 scale

Exclusion Criteria:

• No adverse reaction to study drugs
• Not currently using narcotic analgesic drugs