Stroke
Henry J. Woodford in Essential Geriatrics, 2022
Botulinum toxin can be injected directly into the target muscle, which blocks the release of acetylcholine at nerve synapses. The effects last for around three months. It may be associated with a ‘flu-like illness' immediately after injections. Botulinum toxin injections can reduce spasticity, which can increase range of movement and assist with delivering care, but do not improve function.6 The oral drugs, including baclofen, tizanidine, gabapentin and diazepam, have been tried in the management of spasticity. Although they may have a small effect on reducing spasticity, this is offset by a high incidence of adverse effects, including sedation and weakness.6,100 If tried, people should be monitored for beneficial and adverse effects, with drug withdrawal if there is no net benefit.
Drooling and Aspiration
John C Watkinson, Raymond W Clarke, Christopher P Aldren, Doris-Eva Bamiou, Raymond W Clarke, Richard M Irving, Haytham Kubba, Shakeel R Saeed in Paediatrics, The Ear, Skull Base, 2018
Side effects from botulinum toxin injections are less common than with antimuscarinics.36 The most common and worrying is dysphagia. This is most often a transient phenomenon, lasting just a few days and only apparent if specifically asked about. More severe dysphagia can last for weeks or months and require tube feeding. Reported rates are 7% for transient dysphagia with no intervention required and 3% for severe dysphagia requiring tube feeding.42,48 Children undergoing botulinum toxin injections often have an abnormal swallow to start with but, if they are only just managing to feed orally, botulinum toxin has significant potential to tip them over into a situation where nasogastric feeding is required. Oral feeding may then be difficult to re-establish. Recent international guidelines urge caution in the use of botulinum toxin in children with swallow impairment.20 The ideal candidate for botulinum toxin is the child who is already tube-fed, in which case any transient worsening of swallow is unlikely to have a major impact. For those who are orally fed, the decision to use botulinum toxin is one that should be approached with caution and a full discussion of the potential risks.
Clinical Management of Spasticity and Contractures in Stroke
Anand D. Pandyan, Hermie J. Hermens, Bernard A. Conway in Neurological Rehabilitation, 2018
Nowadays, intramuscular injection of botulinum toxin is an established, well-tolerated, but relatively expensive treatment for focal spasticity. Botulinum toxin prevents the release of acetylcholine from the pre-synaptic nerve terminals, thus blocking the peripheral cholinergic transmission at the neuromuscular junction. This results in reduced muscle contraction. The clinical effects are dose-dependent and temporary. Usually, the effects taper off after 3 to 4 months. Botulinum toxin is injected in the muscle belly of specifically selected muscles. As it diffuses within the muscles, the injections do not have to be placed precisely in the region of motor endplate (of which the exact location is usually unknown), which makes the procedure fairly easy. Nevertheless, ultrasound guided injections are recommended for proper muscle targeting. Adequate dosages and concentrations for spasticity treatment with intramuscular injections of botulinum toxin are extensively described in different guidelines.
Focal arm weakness following intradetrusor botulinum toxin administration in spinal cord injury: Report of two cases
Published in The Journal of Spinal Cord Medicine, 2020
Christopher Goodrich, Henry York, Andrew Shapiro, Peter Howard Gorman
Botulinum toxin is frequently used for managing spasticity, movement disorders, and a variety of other conditions.1 In recent years, the use of botulinum toxin to treat (bladder) detrusor overactivity resistant to anticholinergic medications has grown significantly because the procedure is minimally invasive and offers high rates of symptomatic improvement.2,3 Success rates from this application (including both subjective patient symptom improvement scores and urodynamic measures) are consistently reported as high.3,4 The majority of known side effects of intradetrusor botulinum toxin administration are local in nature (i.e. injection site pain, procedure-related urinary tract infection, hematuria, or increased post-void residuals necessitating new intermittent catheterization).5 Less frequently, systemic side effects including double vision/ptosis, dysphagia, and generalized weakness have been reported.6 Analysis of these cases reveals very little in regards to the risk factors or mechanism related to these effects.7
Pharmacologic therapies for the management of non-neurogenic urinary incontinence in children
Published in Expert Opinion on Pharmacotherapy, 2019
Tiernan Middleton, Pamela Ellsworth
Intradetrusor injection of botulinum toxin is currently FDA approved for use in adults with OAB and neurogenic detrusor overactivityNDO refractory/intolerant to anticholinergic therapy. Botulinum toxin is an acetylcholine release inhibitor and neuromuscular blocking agent. Potency units of botulinum toxin are not interchangeable between the various products available including BOTOX and Dysport. Different forms of botulinum neurotoxin (BoNT) are able to block different proteins on the soluble N‐ethylmaleimide sensitive factor attachment protein receptor (SNARE) complex within cholinergic nerve terminals, which in turn yields cholinergic neuromuscular and autonomic blockade. The longest recorded duration of action through animal studies was with BoNT type A (BoNTA) followed by B, F, and E. It has been theorized that its diffusion to the adjacent muscles might be caused by protein composition, as well as by dilutions, volume, the targeted muscle, and the injection technique.
Abobotulinum toxin A for periorbital facial rejuvenation: impact on ocular refractive parameters
Published in Clinical and Experimental Optometry, 2021
Mohammad H Eftekhari, Hossein Aghaei, Haleh Kangari, Milad Bahrami, Shervin Eftekhari, Seyed M Tabatabaee, Kourosh Shahraki, Mobin Bahrami, Mohammad G Broumand
Facial wrinkles, such as the forehead lines, glabellar wrinkles and crow’s feet lines (lines at the corners of the eye), are created by the contraction of facial muscles. Contraction of the mimic muscles of the face result in the overlying skin moving and forming dynamic wrinkles at 90 degrees to the contraction of muscle direction. The most significant improvement in dynamic wrinkles is observed in patients with injecting botulinum toxin, so these patients can be considered the most appropriate candidates. There are various non‐surgical and surgical facial rejuvenation techniques. The injection of a small amount of botulinum toxin into overactive muscles can relax the muscles. Some side effects of Botox are redness, bruising, haemorrhage, pain at the injection location, infection and inflammatory reaction. Some of these symptoms may indicate an allergic reaction; other allergy symptoms are itching, wheezing, asthma, a rash, red welts, dizziness and faintness. Botox is likely to spread to nearby tissues of the injection site. For instance, temporary droop in the eyebrows or upper eyelids can result from injecting into the forehead around these sites. There are three types of side effects associated with botulinum toxin: (1) the effect expected of this neuromuscular toxin, that is, excessive weakness of the muscle injected; (2) the effect of the diffusion of this neuromuscular toxin to the adjacent non‐injected muscles; and (3) the effect caused by the systemic diffusion of this toxin.8–13