botulinum toxin type a at a glance
Medicine class
A peripherally acting muscle relaxant and neurotoxin.
How it is given
Injected by an appropriately qualified healthcare practitioner into selected muscles or, for sialorrhoea, salivary glands.
What is botulinum toxin type a used for?
Licensed uses differ substantially between products. Selected products cover:
Xeomin: blepharospasm, hemifacial spasm, predominantly rotational cervical dystonia, certain forms of focal limb spasticity and chronic sialorrhoea caused by neurological disorders in adults.
Xeomin: chronic sialorrhoea caused by neurological or neurodevelopmental disorders in eligible children and adolescents.
Azzalure and Relfydess: temporary improvement of specified moderate-to-severe facial lines in eligible adults when they have an important psychological impact.
How does botulinum toxin type a work?
It enters cholinergic nerve endings and prevents release of acetylcholine, which normally activates muscles or glandular secretion. This temporarily reduces local activity until nerve signalling recovers.
botulinum toxin type a preparations and strengths
Injection
Route: Parenteral
Strengths: 50 units, 50 units + 100 units + 200 units, 100 units, 100 units/mL
How to take botulinum toxin type a
A trained healthcare practitioner gives the injection; it is not taken by mouth or self-administered. The practitioner selects the sites through examination and, where appropriate, ultrasound or electromyographic guidance.
Tell the practitioner about previous botulinum toxin treatment, swallowing or breathing problems, neuromuscular conditions, infection near the planned site and all medicines.
Tell the clinic beforehand if you use an anticoagulant or antiplatelet medicine. Do not stop it unless your treating team instructs you.
For spasticity, follow any individual physiotherapy, stretching, splinting or activity plan from your clinical team.
botulinum toxin type a side effects
Common or expected effects
- Pain, tenderness, redness, swelling, bleeding or bruising at the injection site
- Headache
- Temporary weakness of injected or nearby muscles
- Site-dependent effects such as drooping eyelid, dry eye, facial asymmetry or visual disturbance
- Dry mouth or swallowing difficulty with some therapeutic injection sites
Get urgent medical advice
- Difficulty breathing, swallowing or speaking, choking or widespread weakness suggesting distant toxin spread or iatrogenic botulism
- Severe allergic reaction, including facial or throat swelling, breathing difficulty, widespread hives or collapse
- Severe or worsening swallowing difficulty, particularly with aspiration symptoms
- Serious eye pain, marked visual change or inability to close an eye after injections near the eye
botulinum toxin type a in pregnancy
Recommendations vary by product, but selected product information advises avoidance or use only when clearly necessary after specialist assessment. Limited human data have not identified a risk, but cosmetic treatment should be avoided because it has no clinical benefit. Discuss medical treatment with your prescriber if pregnant or planning pregnancy.
botulinum toxin type a while breastfeeding
It is unknown whether these selected products pass into human milk. Their product information advises against use or says use cannot be recommended during breastfeeding, so seek specialist advice before treatment.
botulinum toxin type a interactions
Tell the practitioner about all medicines and recent botulinum toxin injections. Important potential interactions include:
Aminoglycoside antibiotics, such as gentamicin, amikacin or tobramycin
May strengthen neuromuscular blockade and increase muscle weakness.
Neuromuscular-blocking muscle relaxants
The combined effect may cause greater or more prolonged muscle weakness.
Common questions about botulinum toxin type a
Answers are fully visible for fast scanning and source review.
Are all brands the same?
No. Products differ in formulation, licensed uses and potency testing, and their units cannot be interchanged or converted directly.
Does it work immediately?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.