Last reviewed 2026-04-23 · How we verify

onabotulinumtoxinA 24 U

onabotulinumtoxinA 24 U works by temporarily paralyzing muscles to treat muscle spasms and other conditions.

At a glance

Mechanism of action

It does this by blocking the release of acetylcholine, a neurotransmitter that signals muscle contraction. This results in a temporary reduction in muscle activity, which can help alleviate symptoms of conditions such as blepharospasm and cervical dystonia.

Approved indications

No approved indications tracked.

Common side effects

No common side effects on file.

Key clinical trials

• A Study to Evaluate the Effectiveness and Safety of Dysport® for the Prevention of Episodic Migraine in Adults (PHASE3)
• A Study to Evaluate the Effectiveness and Safety of Dysport® for the Prevention of Chronic Migraine in Adults (PHASE3)
• Treatment of Hypertrophic Scars Using Fractional CO2 Laser Alone in Comparison With Adding Botulinum Toxin Either Through Intralesional Injection or Assisted Drug Delivery (NA)
• Study of BOTOX Injections in Prevention of Migraine in Adult Participants With Episodic Migraine (PHASE3)
• Intraoral Administration of Botox in Patients With Dentoalveolar Neuropathic Pain (PHASE2)
• Outcome of Combined Botulinum Toxin A Injection and Gastric Balloon Implantation in Obesity Treatment (PHASE2, PHASE3)
• Safety and Efficacy Study of the Simultaneous Treatment of Upper Facial Lines (Horizontal Forehead Lines, Glabellar Frown Lines and Crows Feet) in Subjects With Moderate to Severe Upper Facial Lines (PHASE3)
• Safety and Efficacy Study of the Simultaneous Treatment of Upper Facial Lines (Horizontal Forehead Lines, Glabellar Frown Lines and Lateral Canthal Lines) in Subjects With Moderate to Severe Upper Facial Lines (PHASE3)

Primary sources

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