New Australian data sheds light on how often patients are concurrently receiving botulinum toxin injections from different providers.
New Australian-first data presented at a recent conference has revealed how many patients receive Botox from multiple providers for different indications, highlighting the risks of concurrent treatments.
Botulinum neurotoxin A (BoNTA) is commonly used to treat muscle contractions and spasms seen in conditions such as incontinence or dystonia and can also be used for cosmetic purposes to treat wrinkles or other aesthetic concerns.
But do you know how many patients you see in your clinic might be receiving BoNTA from other healthcare professionals for different reasons?
This was the question that Dr Libby Buchholz, a GP and cosmetic physician from Geelong, posed to the audience at the recent Australasian Society of Cosmetic and Procedural Dermatologists Symposium in Melbourne.
“A couple of years ago we had a run of three patients in our clinic who came to see us for aesthetic treatment, but they’d also received BoNTA from a therapeutic specialist for a medical problem in the preceding weeks,” Dr Buchholz explained.
One of these patients was seeking aesthetic treatment for facial droop following a basal ganglia stroke – but was also seeing a urologist for bladder hypertonicity and a rehabilitation physician to treat their upper limb muscle spasticity.
“These three patients got us thinking – how many of our patients are going elsewhere and seeing other clinicians [for other BoNTA-related treatments]?” posed Dr. Buchholz.
“There was no Australian data [in the literature], so we decided to try and find out.”
Dr Buchholz and her collaborators conducted a crossover study, where they surveyed eight different practitioners from six different specialties (cosmetic physicians, plastic surgery, urology, neurology, rehabilitation physicians and dentistry).
Participants completed retrospective surveys for 50 consecutive patients or for all patients they had treated over the past six months (whichever came first) and provided data on the five most recent treatments provided to each patient.
Data were collated for 313 patients and 1254 BoNTA treatments. The greatest number of patients were seen by cosmetic physicians (100), followed by plastic surgery, urology and neurology (50 patients each), dentistry (39) and the rehabilitation physician (24).
One in 12 patients (27/313, with 11 coming from the cosmetic physicians, six each from plastic surgery and urology and three from the rehabilitation space) had received BoNTA from different specialists over their past five treatments, a figure Dr Buchholz said was most likely underestimated.
“I was one of the cosmetic physicians who completed a survey for our study, and I know that some of my patients aren’t honest with me when I ask them if they’ve been anywhere else,” she explained.
“They’re embarrassed, and I know for certain they’re not telling some of their medical specialists that they’re seeing me for their [aesthetic treatment].”
Related
More concerning to Dr Buchholz was the finding that one in three patients received BoNTA within 12 weeks of a previous treatment (regardless of the indication) and that one in four patients received a top-up for the same indication within 12 weeks – both of which go against the majority of BoNTA product information guidelines.
“Repeat injections of BoNTA might stimulate the development of neutralising antibodies which counteract the biological activity of BoNTA,” Dr Buchholz told delegates.
“This is known as immunoresistance, and can lead to secondary non-responses, where you need higher doses or more frequent injections to elicit a clinical response.
“And this might be a major problem for some of our patients, if they wake up one day and have a new medical problem that requires BoNTA as a first-line treatment option.”
Rehabilitation physicians were found to use the highest average dose per treatment episode (approximately 375 units per patient), while cosmetic physicians averaged 30-40 units per patient per treatment episode.
A similar pattern occurred when cumulative doses over a 12-month period were estimated. Patients treated by rehabilitation physicians received an average of 1000 units – or 10 vials worth – per year, with some patients receiving as many as 1500 units. Neurology patients received an average of 600 units annually, urology patients 300 units, dentistry patients 190 units, cosmetic physician 140 units and plastic surgery 115 units.
“We can’t really say that this issue doesn’t apply to us as aesthetic practitioners,” Dr Buchholz said.
“Our patients are starting treatments younger and younger. They’re asking for more off-label indications – we’re even doing body contouring now – and our doses are starting to accumulate. The risk profile of our aesthetic patients is starting to approach that of the therapeutic patients.”
Finally, Dr Buchholz noted that different specialists favoured different BoNTA formulations, but emphasised the data were affected by selection bias. Cosmetic physicians and plastic surgeons almost exclusively used incobotulinumtoxinA while neurologists, rehabilitation physicians and urologists tended to use onabotulinumtoxinA and abobotulinumtoxinA.
“In Australia there are PBS subsidies and Medicare rebates for patients with chronic medical conditions so that they can afford treatment, and these complex regulations largely force the hand of our therapeutic specialists,” Dr Buchholz said.
Aesthetic practitioners, on the other hand, have more choice in the formulations they use. This freedom means there is also more opportunity to reduce the risk of immunoresistance and secondary non-responses in the patients they treat.
“Choose to lower your patient’s risk factors,” Dr Buchholz concluded.
“Wherever you can, choose the longest treatment interval… choose the lowest effective dose and the most highly purified formulations with the longest available safety data, and be consistent with your choices.
“[In addition,] communicate with your patients. Ask them if they’ve been anywhere else and coordinate with specialists. Think about whether you need to consent your patients for the development of immunoresistance – is this important medicolegally? [And finally,] make sure you’re asking, ‘since I last saw you, have you had BoNTA anywhere else?’”
Dr Buchholz and her collaborators are preparing their findings for peer review and publication.
The 2026 ASCPD Symposium was held in Melbourne from 20 to 22 March.
