What Is Botulinum Toxin Used For?

Botulism is a deadly form of bacterial food poisoning, but the comercially processed toxin Clostridium botulinum bacteria produce is useful for cosmetic and therapeutic purposes.

Botulinum toxin is a drug produced by Clostridium botulinum, a gram-positive anaerobic bacterium. This is the same toxin that can also cause botulism in the digestive tract from ingestion of contaminated food or an infected wound. 

Botox, a trade name for one of several medical formulations of the toxin, weakens or paralyzes certain muscles or blocks certain nerves. Based on how it’s used, the effects can last for up to a year depending on the condition being treated.

In small doses, botulinum toxin is used for a variety of medical conditions. 

Focal dystonias 

Focal dystonias are Involuntary, sustained, or spasmodic patterned muscle activity. Botulinum-based medications may treat the following focal dystonia types:

• Severe muscle contractions in the neck (cervical dystonia, spasmodic torticollis) 
• Eyelid spasm/closure (blepharospasm) 
• Muscle spasms of the vocal cords (laryngeal dystonia/spasmodic dysphonia) 
• Writer's cramp (limb dystonia)
• Muscle spasm of the face, jaw, and/or tongue (oromandibular dystonia, orolingual dystonia)
• Muscle contractions in the trunk (truncal dystonia)

Spasticity

Various conditions cause muscles to tighten and stiffen, that is, become spastic. These include

• Stroke  
• Traumatic brain injury 
• Cerebral palsy
• Multiple sclerosis
• Spinal cord injury

Non-dystonic disorders 

Other types of disorders may also result in involuntary muscle activity:

• Twitching of muscles on one side of the face (hemifacial spasm)
• Tremor 
• Tics 
• Muscle twitching and involuntary muscle movement (myokymia and synkinesis)
• Ringing in the ears (tinnitus) (due to myoclonus of stapedius muscle and tensor veli palatini muscle)
• Hereditary muscle cramps
• Nocturnal tooth grinding (bruxism) 
• Lockjaw (trismus)
• Failure of the anal sphincter to relax during defecation (anismus)

Ocular uses 

• Crossed eyes (strabismus) 
• Involuntary eye movement (nystagmus)

Chronic pain and disorders of localized muscle spasms

• Chronic low back pain
• Myofascial pain syndrome 
• Tension headache 
• Chronic migraine headache 
• Medication overuse headache 
• Tennis elbow (lateral epicondylitis)
• Knee pain 
• Shoulder pain 
• Neuropathic pain 

Smooth muscle hyperactive disorders

• Neurogenic bladder; Detrusor hyperreflexia (urinary urgency)
• Detrusor-sphincter dyssynergia (problems with urination)
• Enlarged prostate (benign prostatic hypertrophy, BPH) 
• Problems with the esophagus that make it hard to swallow (achalasia cardia)
• Hirschsprung disease 
• Sphincter of Oddi dysfunctions 
• Hemorrhoids 
• Chronic anal fissures 
• Raynaud's Phenomenon (constriction of bloodflow to extremities)

Cosmetic use

• Hyperkinetic facial lines (glabellar frown lines, crow's feet) 
• Hypertrophic platysma muscle bands 

Sweating, salivary, and allergy disorders

• Excessive sweating of the armpits and palms (axillary and palmar hyperhidrosis)
• Frey syndrome, also known as auriculotemporal syndrome (gustatory sweating of the cheek after parotid surgery)
• Drooling in cerebral palsy and other neurological disorders 
• Nasal allergy and allergic rhinitis

Botulinum toxin is categorized into seven neurotoxins (labeled as types A, B, C [C1, C2], D, E, F, and G), which are structurally similar but possess some individual differences. Drug names have been established by the Food and Drug Administration (FDA) to help reinforce the differences and prevent medication errors.

The following are examples of botulinum toxin products along with their approved medical uses:

• OnabotulinumtoxinA (Botox, Botox Cosmetic)
  • Botox is used to treat
  • Cervical dystonia
  • Severe primary axillary hyperhidrosis
  • Crossed eyes (strabismus)
  • Eyelid twitching (blepharospasm)
  • Involuntary contractions of the bladder muscle (neurogenic detrusor overactivity)
  • Chronic migraine
  • Upper limb spasticity
• Botox Cosmetic is used to treat 
  • Moderate to severe glabellar lines (forehead furrows)
  • Moderate to severe lateral canthal lines (crow’s feet)
• AbobotulinumtoxinA (Dysport) is used to treat 
  • Upper and lower limb spasticity
  • Cervical dystonia
  • Moderate-to-severe glabellar lines in adults
  • Lower limb spasticity in children aged 2 years or older
• IncobotulinumtoxinA (Xeomin) is used to treat
  • Upper limb spasticity
  • Cervical dystonia
  • Blepharospasm
  • Moderate to severe glabellar lines
  • Drooling/excess salvia (chronic sialorrhea)
• PrabotulinumtoxinA (Jeuveau) is used to treat
  • Moderate-to-severe glabellar lines
• RimabotulinumtoxinB (Myobloc) is used to treat
  • Cervical dystonia

The most common side effects of botulinum toxin include

• Injection site reactions (such as pain, swelling, or bruising)
• Flu-like symptoms
• Headache
• Upset stomach
• Temporary drooping eyelids (when injected into the face)
• Facial and other muscle weakness
• Respiratory problems
• Problems swallowing 
• Seizures