This study investigates the effectiveness of a sublingual investigational medication in treating acute pain for adult patients with bone fractures in their limbs. Acute pain is a sudden and sharp pain that can occur due to injuries like bone fractures. The study aims to evaluate whether this method of delivering medication under the tongue can effectively manage such pain conditions.

Participants will receive either the investigational medication or a placebo, which is an inactive substance that looks like the investigational medication but does not contain any medicine. The study will involve monitoring pain levels using a numerical rating scale to assess the medication's effectiveness.

• Who can participate: Adults over 16 years old with a clinical diagnosis of extremity bone fracture and an acute pain score of 3 or greater on a numerical rating scale can participate. Individuals with long-term opioid use, known sensitivity to opioids, pregnant women, or those with certain medical conditions are excluded.
• Study details: Participants will be assigned to receive either the investigational medication or a placebo. The study will measure pain levels using a numerical rating scale to determine the effectiveness of the treatment.