Skip to Main Content

++

BACKGROUND

++

Botulinum toxins are neurotoxins produced by the gram-positive, spore-forming, anaerobic bacteria, Clostridium botulinum, as well as C butyricum, C baratii, and C argentinense.1,2 These toxins are the most deadly human neurotoxins known. Clinically, botulism can occur following ingestion of contaminated food or from a wound infection. The clinical signs of botulism include limb paralysis, facial weakness, ophthalmoplegia, dysarthria, dysphagia, dyspnea progressing to respiratory arrest, constipation progressing to ileus, and urinary retention.3 C botulinum produces 7 antigenically (immunologically) distinct neurotoxins: A, B, C1, D, E, F, and G.

++

  • Varied mechanisms of action of botulinum neurotoxin (BoNT) subtype are believed to be due to its ability to inhibit multiple neurotransmitters from presynaptic vesicles. Specific proteins involved in this process are affected by different toxins and thus different strains of toxin do not necessarily work via the same mechanism.

  • Only types A and B toxin are currently routinely used in clinical practice.

  • Currently, there are 3 types of botulinum toxin type A commercially available in the United States including onabotulinum toxin A (Botox), abobotulinum toxin A (Dysport), and incobotulinum toxin A (Xeomin).

  • Rimabotulinum toxin B (Myobloc) is the only botulinum toxin type B currently available in the United States.

  • Each toxin has been developed with different dosing units and they are not interchangeable—this is clinically important to remember. Synaptosomal-associated protein (SNAP 25) is inactivated by botulinum toxin type A and vesicle associated membrane protein (VAMP) is inactivated by botulinum toxin type B.

  • Its effect on motor function through inhibition of release of acetylcholine has been well documented. Cleavage of either one of these proteins results in inhibition of acetylcholine release, disruption of neuromuscular transmission, and paralysis of the muscle.

  • Most important recent scientific discovery is of SNAP 25 on motor and sensory neurons.

  • Several animal studies demonstrating the toxin’s inhibition of substance P, calcitonin-gene related peptide (CGRP), glutamate, bradykinin, ATP, and purinergic receptors.

  • Additional animal studies have suggested a clinically relevant central analgesic effect of type A toxin as well.

++

The only FDA-approved specific pain indication for any current commercially available botulinum toxin is chronic migraine for onabotulinum toxin A (Botox).4 The “off-label” use of botulinum toxin for the treatment of other chronic painful conditions has been reported for cervical dystonia–associated neck pain, chronic low back pain, and chronic lateral epicondylitis. Jabbari and Machado have recently published a review of the use of botulinum toxin for refractory pain based on the evidence according to the AAN evidence rating approach. The reader can review these references for additional information regarding the use of botulinum toxins for chronic pain.

++

BOTULINUM TOXIN FOR THE TREATMENT OF CHRONIC MIGRAINE

++

The most evidence for treatment with botulinum toxin is for the specific condition, chronic migraine. The importance of defining this group has become vital for proper patient selection. The FDA has approved the use of onabotulinum toxin ...

Want remote access to your institution's subscription?

Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.

Ok

About MyAccess

If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.

Subscription Options

AccessAnesthesiology Full Site: One-Year Subscription

Connect to the full suite of AccessAnesthesiology content and resources including procedural videos, interactive self-assessment, real-life cases, 20+ textbooks, and more

$995 USD
Buy Now

Pay Per View: Timed Access to all of AccessAnesthesiology

24 Hour Subscription $34.95

Buy Now

48 Hour Subscription $54.95

Buy Now

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.