This article, featuring the Tsang/Shidlofsky Visual Snow Protocol discussed at the VSI Virtual Summit 2022, was originally published on rxisk.org.
Visual snow describes the appearance of flickering dots or “static” in the field of vision. It’s thought to be a problem with visual processing rather than a structural issue within the eyes. This can cause difficulties for patients when trying to report visual snow to their doctor, as standard eye examinations typically find no abnormalities in these patients.
The problem can be accompanied by other visual symptoms including palinopsia (afterimages), sensitivity to light (photophobia), flashes (photopsia), and floaters. Non-visual symptoms have also been reported including ringing in the ears (tinnitus), a feeling of depersonalization, and cognitive impairment. When there are other symptoms in addition to the visual snow itself, this is classified as visual snow syndrome.
There doesn’t appear to be a single cause of the condition, and in many cases there is no obvious explanation for its onset.
Visual snow and antidepressants
Our interest in the condition stems from receiving reports of visual snow syndrome linked to the use of SSRI and SNRI antidepressants. In many cases, the problem didn’t go away when the person stopped the medication, and in some cases their vision worsened upon stopping.
This appears to follow the same pattern as post-SSRI sexual dysfunction (PSSD) in that sexual side effects can remain after stopping an antidepressant, or sometimes only emerge when the medication is stopped. It also follows the pattern of tardive dyskinesia, a movement disorder linked to antipsychotics which can appear on treatment and remain afterwards, or only appear when the drug is stopped.
Ironically, patients with visual snow syndrome are sometimes given antidepressants in an attempt to help their condition – usually without success.
There were 11 reports of visual snow syndrome in our recently published paper: Development and persistence of patient-reported visual problems associated with serotonin reuptake inhibiting antidepressants. You can read the accompanying blog post here.
There is no suggestion that SSRIs or related medications are responsible for all cases of visual snow, but the data does suggest that these drugs can cause the condition in some patients.
At the time of writing our paper, we had 11 reports of visual snow syndrome linked to antidepressants. We now have 14 reports.
We are interested to hear from anyone with visual snow (or any vision problem) linked to the current use or previous use of an antidepressant. Please leave a comment below. You can also report your condition to us by completing a RxISK Report even if you aren’t interested in taking the report to your doctor.
Visual Snow Initiative
The Visual Snow Initiative (VSI) was founded by Sierra Domb, herself a sufferer of visual snow syndrome. The organisation works towards raising awareness, providing education, and carrying out research. They provide a lot of information about the condition on their website including diagnostic criteria and descriptions of the symptoms. The image at the top of this blog post is from their website.
We sent details of our published paper to the VSI, and they very kindly included it in their news section. They also informed us about a forthcoming announcement of a new treatment.
The announcement was made at the Visual Snow Initiative Virtual Summit 2022. The video is available to watch at the end of this blog post.
The treatment was developed by Dr. Terry Tsang and Dr. Charles Shidlofsky, both based in the US. They had been working separately with patients who had visual snow syndrome and had both independently developed a method of treating the condition. They were put in contact with each other by the VSI and discovered that their treatment methods followed a similar approach. They began working together to refine the treatment and to run a study, the results of which are discussed in the video.
Patients undergo a set of specialized visual tests, and the treatment is tailored to each patient depending on the specifics of their condition. The treatment consists of a series of visual exercises that help to strengthen certain aspects of visual processing. Rather than go into too much detail here, it would be better for anyone with visual snow syndrome or anyone with an interest in these issues to watch the video.
We understand from the VSI that the treatment helps symptoms regardless of the origin of the condition. The study group apparently contained several participants that were on antidepressants, and their symptoms improved.
Following the announcement, we’ve had some contact with Dr. Shidlofsky. We’ll let you know if there is anything further to report.
Visual snow is interesting in its own right but also because of its possible connection to PSSD and antidepressant withdrawal.
Could the same mechanisms underpin all three and other sets of related problems?
Does this new visual snow treatment point to anything that could be done for people with PSSD or psychotropic drug dependence?