Botulinum Toxin Effectively Manages Epiphora

Patients who received Botox injections saw a mean reduction in Schirmer score of 8.8mm at three months. Note, however, that Botox has the ability to diffuse up to 45mm from injection site, crossing anatomical barriers like the orbital septum, and this local diffusion and subsequent chemodenervation is likely contributing to adverse effects like ptosis that can manifest. Photo: Joseph Sowka, OD. Click image to enlarge. Lacrimal gland injections can be a good option for patients who experience excessive tearing. Although epiphora may be seen as minor, an individual’s quality of life may be reduced due to visual blurring or social embarrassment. One systematic review was conducted by researchers to evaluate the safety and efficacy of using botulinum toxin (Botox) injections as a less invasive treatment for patients who suffer from this condition. The paper was published last week in Ophthalmic Plastic & Reconstructive Surgery.Included in the meta-analysis were 19 studies that met the inclusion criteria, comprising data on 415 patients injected with Botox. It was found that Schirmer test scores decreased at three months, with a mean difference of 8.8mm, as well as having decreased at six months, but with a smaller mean difference of 5.3mm. Adverse event overall incidence was 22%, with the most common being ptosis (63%) and diplopia (21%). Reinjection was also found to be more common in the functional epiphora group (81%) than the nonfunctional group (43%); mixed presentation fell in the middle with 57%, and in all, 64% of patients received reinjection.Despite the mild decrease in efficacy seen from three to six months, the authors elaborate in their paper that this decline is expected due to the transient effects of Botox—especially without repeated injections. Other than the objective measurement of Schirmer scores, subjective patient-reported outcomes also displayed significant improvement, reflective of high patient-reported satisfaction.Therapeutically, the effect of Botox is achieved via inhibition of acetylcholine at the neuromuscular junction within the lacrimal gland, which in turn causes transient, controlled tear output reduction from partial glandular paralysis. With functional epiphora, this mechanism is especially beneficial, since excessive tearing is caused by a hyperactive lacrimal gland independent of anatomical obstruction. The reason why a prolonged effect of botulinum toxin seems to occur on autonomic synapses in the lacrimal glands compared with neuromuscular synapses is not fully understood.The authors also touch on the disparity of reinjection rates in the different subgroups of epiphora, which could reflect differences in perceived patient benefit and tolerability. One previous study found reinjections were primarily patient-driven at variable intervals, indicating the lower injection rate in the nonfunctional group of the current study could mean fewer patients experienced sufficient or lasting improvement enough to facilitate another injection. Another reason may be due to mild or transient adverse effects, coupled with the temporary nature of the therapy, deterring individuals from committing to repeated treatment. Along with other reasons, the authors suggest that this “highlight[s] the need for individualized counseling and longitudinal assessment of treatment satisfaction when considering repeat injections.”In general, though, they believe botulinum toxin injection “stands as a promising option for select patients, offering a balance of efficacy, reversibility and low invasiveness in managing chronic epiphora.”Click here for the journal source. Alfarhan A, Alsubhi A, Daghistani G, et al. Efficacy and safety of botulinum toxin injections for epiphora management: a systematic review and meta-analysis. Ophthalmic Plast Recontr Surg. July 3, 2025. [Epub ahead of print].