What is the primary therapeutic use of the drug Oxybutynin?

Oxybutynin is primarily used to treat overactive bladder, a condition characterized by symptoms such as frequent urination, urgency, and in some cases, urge incontinence. This medication falls under the category of anticholinergic agents, which work by blocking the action of acetylcholine on muscarinic receptors in the bladder. By doing so, oxybutynin reduces bladder contractions, leading to increased bladder capacity and decreased urgency.

While the other options represent valid medical conditions that require specific treatments, they are not the primary therapeutic uses of oxybutynin. Chronic obstructive pulmonary disease and Parkinson's disease involve different pharmacological approaches, while acid reflux is managed with medications that suppress gastric acid secretion, not anticholinergic agents. Thus, the most accurate indication for oxybutynin's use is in managing overactive bladder symptoms.