This study looks at using **Botulinum Toxin A (BoNT-A)** to treat **overactive bladder** in people with **Parkinson's Disease (PD)**. An overactive bladder makes you feel like you need to pee a lot, even at night. This is common in PD, affecting how often you need to use the restroom and can disturb sleep. The study involves injecting a small dose of BoNT-A into the bladder muscle. This is believed to be safe and helpful, especially for those who do not get better with regular medication.

**Key Points:**

• The study will include adults with Parkinson's Disease aged 25-80.
• Participants must keep the same dose of any bladder medicine they are already taking during the study.
• People with certain medical conditions, like glaucoma or allergies to the study drug, cannot join.