Subcutaneous Botulinum Toxin for Cutaneous Allodynia

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00725322
Recruitment Status : Completed
First Posted : July 30, 2008
Results First Posted : October 25, 2017
Last Update Posted : October 25, 2017
Information provided by (Responsible Party):
Sean Mackey, Stanford University

Brief Summary:
Superficial injection of Botulinum toxin has been advocated for cosmetic purposes but has also been reported to be helpful for some pain conditions. The investigators have observed prolonged profound analgesia following subcutaneous superficial injection of Botulinum Toxin Type A (BTA) in patients with certain types of neuropathic pain. The investigators propose to study if addition of BTA extends pain relief compared to placebo when injected subcutaneously into areas of cutaneous allodynia (the property that a normally non-noxious stimulus is perceived as painful).

Condition or disease Intervention/treatment Phase
Pain Drug: Botulinum Toxin A Drug: Placebo - Saline Not Applicable

Detailed Description:

Post-surgical neuromatous pain patients have marked cutaneous allodynia. Touching their skin with normally non-painful stimuli results in pain. Injected local anesthetics are often effective in providing temporary relief. In the course of clinical practice the investigators have observed that a number of patients with cutaneous allodynia have had marked persistent benefit from subcutaneous injection of Botulinum toxin Type A.

Rather than killing targeted neurons, Botulinum toxin type A inhibits release of acetylcholine from cholinergic nerve terminals in a prolonged but ultimately reversible manner. Neuropathic pain and its hallmark allodynia are classically difficult to treat. Standard treatment with tricyclic antidepressants, anti-epileptic drugs, opiates and spinal cord stimulation is frequently disappointing leaving patients with refractory pain. Surgical or percutaneous ablation of involved nerves has fallen out of favor among many due to disappointing results.

A pilot study is needed to assess the efficacy of superficially injected Botulinum Toxin type A for treatment of cutaneous allodynia and spontaneous pain among patients with neuropathic pain.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 84 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Subcutaneous Botulinum Toxin for Cutaneous Allodynia
Study Start Date : December 2007
Actual Primary Completion Date : March 2013
Actual Study Completion Date : March 2013

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Botox
U.S. FDA Resources

Arm Intervention/treatment
Experimental: Placebo then Botox Drug: Placebo - Saline
Subcutaneous Saline injection given at site of scar neuroma
Experimental: Botox then Placebo Drug: Botulinum Toxin A
Subcutaneous injection of Botulinum Toxin Type A into the patient's scar tissue

Primary Outcome Measures :
  1. Time Until Analgesic Failure [ Time Frame: Each participant was assessed for up to 224 days per intervention (injection) or until they returned to NRS baseline ]
    Participants made daily NRS reports via Palm Pilot, and "failure" was defined as (Pre-injection baseline NRS) - (Mean NRS for any 3 preceding days) ≤ 0; or 9 months

Secondary Outcome Measures :
  1. NRS Score Three Weeks After Injection [ Time Frame: Three weeks after injection ]
    The NRS scores range from 0-100, where 0 indicated no pain and 100 indicated the worst pain.

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Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:- Moderate to severe pain (greater than 4/10) of duration more than 6 months despite previous therapy.

  • The patient exhibits at least 80% pain relief following injection of local anesthetic subcutaneously into scar as assessed by change in NRS
  • The patient reports the presence of hyperalgesia, allodynia, dysesthesia, or hypoesthesia surrounding the scar
  • Age 18-100
  • Ability to read, write, and converse in English, provide informed consent, and follow study procedures

Exclusion Criteria:

  1. Any neuromuscular disorder such as myasthenia gravis, eaton lambert, muscular dystrophy
  2. Any ongoing legal action related to their pain
  3. Allergy to local anesthetics
  4. A current or history of any severe psychiatric disorder
  5. History of any adverse reaction to botulinum toxin
  6. History of botulism
  7. Untreated infection
  8. Coagulopathy
  9. Females - positive pregnancy test
  10. Surgery within the past 6 months at the site of the painful scar

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00725322

United States, California
Stanford University School of Medicine
Stanford, California, United States, 94305
Sponsors and Collaborators
Stanford University
Principal Investigator: Ian R Carroll Stanford University
Principal Investigator: Sean Mackey Stanford University

Responsible Party: Sean Mackey, Assistant Professor, Stanford University Identifier: NCT00725322     History of Changes
Other Study ID Numbers: SU-01072008-965
First Posted: July 30, 2008    Key Record Dates
Results First Posted: October 25, 2017
Last Update Posted: October 25, 2017
Last Verified: October 2017

Additional relevant MeSH terms:
Somatosensory Disorders
Sensation Disorders
Neurologic Manifestations
Nervous System Diseases
Signs and Symptoms
Botulinum Toxins
Botulinum Toxins, Type A
Acetylcholine Release Inhibitors
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action
Cholinergic Agents
Neurotransmitter Agents
Physiological Effects of Drugs
Neuromuscular Agents
Peripheral Nervous System Agents