Clostridium botulinum

This Daily Doodle represents the medical uses of the powerful neurotoxin produced by Clostridium botulinum and it also serves as a review of the intricate anatomy of the facial muscles.

Clostridium botulinum is a obligate anaerobe, spore-forming, gram-positive, rod-shaped bacteria that produces eight types of toxins, lettered A to H. The botulinum toxins, BTX-A and B, are available commercially for various cosmetic and medical procedures.

The botulinum toxin is well known for its potentially life-threatening paralytic condition after consuming improperly preserved food containing the toxin. Thankfully, botulism poisoning is rare in Canada with only about two cases per year (3). But, with that said, always think twice about eating questionable canned food and error on the side of caution. For further information, Health Canada has provided a list of precautions to reduce the risk of BTX poisoning.

The mechanism of action of BTX is featured in the top right corner of this Daily Doodle. BTX prevents muscular contraction by blocking the release of acetylcholine from peripheral nerve cells into the neuromuscular junctions. Understanding the mechanism of action of BTX has allowed researchers and clinicians to discover new uses and clinical applications. See below for a comprehensive list of clinical uses of BTX.

The botulinum toxin is also well known for its use for cosmetic indications, which was first reported and published by a Canadian husband and wife team, Drs. Carruther (dermatologist and ophthalmologist) in 1992.

The use of BTX-A for cosmetic indications requires an in-depth understanding of the facial anatomy including the origin and insertion of the muscles, their vector of pull and the common anatomical variations. This Daily Doodle captures a few of the major facial muscles that can be treated using BTX.

The  multiple drops in this Daily Doodle represent the multiple clinical uses of BTX, in particular hyperhidrosis (increased perspiration/sweating), and the Maple Leaf is to symbolize the contributions of the Canadian Team Drs. Carruther and their published findings.


Botulism Botox Michiko Maruyama Daily Doodles


The article ” Uses of botulinum toxin injection in medicine today” published in BMJ provides a comprehensive list of the various uses of BTX, including (4):

Disorders caused by overactivity of muscles for which treatment with botulinum toxin A is established

Ophthalmological disorders: Concomitant misalignment, Primary or secondary esotropia or exotropia, Nonconcomitant misalignment, Paralytic strabismus (III, IV, VI nerve palsy,internuclear ophthalmoplegia, skew deviation), Duane’s syndrome, Restrictive or myogenic strabismus

Movement disorders: Idiopathic focal dystonias, Craniocervical (torticollis and isolated head tremor,blepharospasm, oromandibular dystonia, lingualdystonia, laryngeal dystonia), Other focal dystonias (writer’s cramp, occupationalcramps such as musician’s cramp), Tardive dystonia, Hemifacial spasm/post-facial nerve palsy synkinesis


Examples of overactive muscle conditions for which treatment with botulinum toxin A has been tried

Ophthalmic disorders: Disorders of ocular motility (nystagmus and oscillopsia), Thyroid disease (upper eyelid retraction, glabellar furrowing), Therapeutic ptosis for corneal protection

Movement disorders: Secondary dystonia, Tic disorders (simple tics, Tourette’s syndrome, dystonic tics), Tremor (essential, primary writing, palatal, cerebellar), Painful spinal myoclonus, Parkinson’s disease (freezing of gait, off period dystonia, severe constipation), Cephalic tetanus, stiff man syndrome, neuromyotonia, Muscle stiffness, cramps, spasms

Spasticity: Multiple sclerosis, Stroke, Traumatic brain injury, Cerebral palsy, Spinal cord injury

Neuromuscular disorders: Myokymia, Neurogenic tibialis anterior hypertrophy with myalgia, Benign cramp-fasciculation syndrome

Pain: Headache (tension type, migraine, cervicogenic), Backache (neck, lower back), Myofascial pain, Tennis elbow

Ear, nose, and throat disorders: Oromandibular disorders (bruxism, Masseter hypertrophy,temporomandibular joint dysfunction), Pharyngeal disorders (cricopharyngeal dysphagia, closure of larynx inchronic aspiration), Laryngeal disorders (vocal fold granuloma, ventricular dysphonia,mutational dysphonia), Stuttering with glottal blocks

Disorders of pelvic floor: Anismus, Vaginismus, Anal fissures, Detrusor-sphincter dyssynergia

Cosmetic applications: Wrinkles, frown lines, Rejuvenation of ageing neck




  1. J. Carruthers and A. Carruthers. “Overview of botulinum toxin for cosmetic indications.” April 2, 2014.
  2.  K. Todar. “Pathogenic Clostridia, including Botulism and Tetanus.” Todar’s Online Textbook of Bacteriology.
  3. Public Health Agency of Canada. “Botulism.”
  4. A Münchau and K P Bhatia. “Uses of botulinum toxin injection in medicine today” BMJ. Jan 15, 2000; 320(7228): 161–165.
  5. J. Finn and S. Cox. “Practical Botulinum Toxin Anatomy.” April 2, 2014.


April 2, 2014 – “Clostridium botulinum” Daily Doodle by Michiko Maruyama


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