Onabotulinumtoxin A
Neurotoxin, neuromuscular blocker (presynaptic)
Onabotulinumtoxin A
Botox
Onabotulinumtoxin A (brand name Botox) is a purified neurotoxin derived from Clostridium botulinum. FDA-approved in 2010 for chronic migraine prophylaxis (≥15 headache days/month, ≥8 of which are migraine), administered via the PREEMPT injection protocol across 31 fixed sites in head and neck musculature every 12 weeks.
Experience
No personal reports yet
No clinical reports yet
Log in to add your own experience.
Problems
No problems yet. Be the first to suggest one.
+ Add a problemTitration strategies
No titration strategies yet. Be the first to suggest one.
Effects
No effects listed yet. Be the first to suggest one.
Relevant anecdote
No anecdotes yet. Share a relevant one.
Relevant Literature
No literature entries yet.
Log in to submit relevant literature.
Summary
Classes
Neurotoxin, neuromuscular blocker (presynaptic)
Common uses
Chronic migraine (≥15 headache days/month), cervical dystonia, blepharospasm, hyperhidrosis, overactive bladder, urinary incontinence, strabismus, spasticity, cosmetic indications
Pharmacy
Starting dose
Chronic migraine (PREEMPT protocol): 155 units divided across 31 sites in 7 head/neck muscle groups every 12 weeks
Preparations
50, 100, or 200 unit vials of lyophilized powder for reconstitution
US FDA Max
195 units/treatment for chronic migraine; max varies by indication
Pharmacology
Routes
Intramuscular (PREEMPT injections for migraine)
Onset
1–2 weeks for muscle effects; preventive migraine benefit accrues over 12-week cycles
Duration
~12 weeks
Half-life
Tissue half-life not formally measured; clinical effect ~12 weeks
Bioavailability
Local (intramuscular)
Pregnancy
Category C; limited data
Legal status
Rx; black-box warning for distant spread of toxin effect
Purported mechanism
Cleaves SNAP-25 protein in presynaptic motor and autonomic nerve terminals, blocking acetylcholine release; in chronic migraine, hypothesized to inhibit peripheral sensitization of trigeminovascular nociceptors