Do you find onabotulinumtoxinA injections effective for the treatment of trigeminal neuralgia?

I use botulinum toxin (off-label) for two face pain conditions, one rare, i.e., trigeminal neuralgia, and one common, i.e., temporomandibular disorder (TMD). For trigeminal neuralgia, I use a tiny needle to inject very small amounts of the toxin into the affected area of the skin and, if involved in the pain as well, also in the gum. For temporomandibular disorder, I palpate for taut bands in the masseter muscle(s) that I inject, generally 5 units per injection and 5-7 injections per muscle.

I've had a very similar experience with Dr. @Dr. First Last, treated several at least dozens, perhaps (>)> 100 patients with trigeminal nerve pain in my former clinics at Duke. There were approximately ½ of those who suffered neuralgic attacks, most with underlying continuous pain, and very few with "clean" neuralgia only.

From both ends, the treatment was perceived as safe and effective, and patients kept coming back, many traveling long distances.

How did I administer it? I injected typically 100 units in 10 U aliquots subcutaneously (or submucosally for intraoral targeting) into the territory of the affected trigeminal branch, following a principle of "deposit it where it hurts", but also feeding it into nerve endings of the same branch th...

For TMJ disorders (TMJD), I administer low-dose Botox injections into both the temporalis and masseter muscles, targeting 2-3 sites per muscle dose depending on the severity of symptoms and muscle size. For trigeminal neuralgia, I use a superficial injection technique, applying Botox in a grid-like pattern on the affected facial area, typically 1-2 units per site. In my experience, Botox has yielded consistently good results for TMJD, while the outcomes for trigeminal neuralgia have been mixed. However, approximately two-thirds of my trigeminal neuralgia patients report some symptom improvement. For long-term Botox injections into the masseter muscles, it is important to monitor for signs of muscle atrophy and adjust the dosage as needed to...

I have never used it. From a quick literature review, there is limited evidence for efficacy. There have been case reports/series, and small prospective observational studies. There is a recent meta-analysis by Hu et al., PMID 38385501, where they reported four RCTs and several observational studies with the primary outcome of VAS showing improvement. Patients were followed for up to 12 weeks. They reported that Botox was primarily injected intradermally and or submucosally at the site of pain and the trigger point. In many trials, injections were administered at multiple sites, with intervals of 10 or 15 mm apart from each other. Two studies targeted the sphenopalatine ganglion.

I practice in Western Pennsylvania and I do not believe that ...

I use onabotulinumtoxinA in patients with trigeminal neuralgia who have not responded to first-line treatments. Usually, I will have tried carbamazepine or oxcarbazepine, lamotrigine, and gabapentin/pregabalin at least before trying. I particularly try if surgical treatment is not an option. I have seen it be beneficial and the resulting facial weakness is much less than I often expect.

I usually inject V2 or V3 pain along the line where they feel the paroxysms, dosed as 2.5u spaced out by about 1 finger breadth. Often, the reason it gets covered is that they have comorbid migraine, so I dose at least 40u in the ipsilateral temporalis.

Good recent systematic review: Hu et al., PMID 38385501.

Botox is not covered by insurance for trigeminal neuralgia in the US, nor is TMJ, so its use is limited in general.

I use spinal cord stimulation (SCS) for trigeminal neuralgia, and it has been a life-changing procedure for most of my trigeminal neuralgia patients, after years of failed attempts at medications and potentially decompression surgeries.

Gupta et al., PMID 35716273

The trial procedure is relatively safe and can be done in the clinic without any sedation. Patients would notice whether there is pain relief within a few days. The system won't be implanted unless they receive >50% pain relief during the trial.

The implantation procedure is also relatively non-invasive, fully reversible when done with a percutaneous approach by an int...

I have been using onabotulinumtoxinA for TN for years with generally good results. I typically consider it for patients who have either failed to respond adequately to first-line treatments or who prefer to avoid the long-term use of systemic medications.

Overall, I have found it to be clinically beneficial in a substantial proportion of patients. While response rates can vary depending on disease severity and prior treatment history, it can serve as an effective adjunctive or alternative option in selected patients with refractory TN.