Nova Scotia is the latest of places where pharmacists are allowed to prescribe a one dose prophylactic upon a known tick bite, within 72 hours of the bite, and if there are no symptoms.
Unfortunately, many see this as a good news story, but I’m not so sure.
The following is a Canadian research document from 2019 regarding the single dose prophylactic- https://www.ncbi.nlm.nih.gov/books/NBK545493/. If I am reading this document correctly, the decision to provide this one dose prophylactic is based on limited, and outdated, data. The recommendation in the document is “Further high-quality studies are needed to confirm the results of this RCT with appropriate enrollment and follow-up of a validated outcome in a generalizable setting. Ideally this research would be conducted in Canada to inform Canadian clinical decision-making and policy making.”
So, why are we promoting it now? Before more studies/research is undertaken?
As well, there is information available that suggests this single dose prophylactic may only prevent a rash. However, it should be noted that only about 80% actually get a rash and of that 80% many don’t see it or don’t realize that there are other types of erythema migrans rashes. It’s not just a bull’s-eye rash. We also don’t know if it is effective for co-infections, of which there are many in Nova Scotia.
As well, apparently antibiotics can interfere with future Lyme testing, resulting in difficulty in getting diagnosed – https://www.canada.ca/content/dam/hc-sc/migration/hc-sc/dhp-mps/alt_formats/pdf/medeff/bulletin/carn-bcei_v22n4-eng.pdf.
This topic is not new. In 2019, the following article was written by another Nova Scotia resident, with better credentials than I – https://www.saltwire.com/nova-scotia/opinion/counterpoint-theres-no-evidence-quick-dose-of-antibiotics-will-stave-off-lyme-309057/.
The use of this prophylactic has been used in other areas for quite some time now. The following is an article from Rhode Island – https://www.pharmacytoday.org/article/S1042-0991(17)31328-2/fulltext?. It’s interesting to note that it mentions that it is not 100% guaranteed to work and that people need to be aware of that. I’m not sure that this fact is being adequately communicated. I’m also not sure if any follow-up is being provided to ensure that people remain symptom free.
If this prophylactic treatment does not work, and subjective, rather than objective, symptoms appear, it may be very difficult to obtain a diagnosis as most doctors require visible, objective, symptoms prior to a diagnosis and treatment. Even some possible objective symptoms, such as bell’s palsy; swollen, inflamed joints; heart block; etc., are not always considered to potentially be the result of a tick bite, especially in areas newer to Lyme carrying ticks.
Another concern with this prophylactic treatment is that pharmacists need to see the tick and if the tick is taken in to the pharmacist it may be disposed of rather than tested for any pathogens. Although it appears that the only tick testing being undertaken in Canada at the moment is at Geneticks, which is a private lab and testing is for a fee, I highly recommend that people have ticks tested that were attached to a human, or pet, and were either removed incorrectly (body squeezed) or engorged. As there are a number of things that have been found in ticks (both blacklegged and dog) in the province, I suggest the full panel. This tests for a number of things, most, if not all, of which have been found in the province.
Please do your research prior to agreeing to the one dose prophylactic.