It Just Ticks You Off

Rocky Mountain Wood Tick (Dermacentor andersoni) (Adult) — Adult Rocky Mountain Wood Tick (Dermacentor andersoni),
forcibly detached from WC in 2017

Tick season is about to start.

Ticks in Idaho spread among other diseases, West Nile virus, Rocky Mountain Spotted Fever, tick-borne relapsing fever and tularemia. Lyme disease gets all the press, but so far the tick species that transmits Lyme disease, Western Blacklegged Tick, is found only in North Idaho. Still who wants a blood-sucking arthropod dug into their skin, even if it’s giving you something other than Lyme disease?

We can protect our pets. Lotilaner is a drug that paralyzes and kills fleas and ticks by interfering with the way that signals are passed between their nerve cells. Lotilaner is approved as a veterinary medicine under the brand name Credelio to control fleas and ticks in dogs and cats. Lotilaner works because it acts on ticks at the first blood they ingest; the infectious agents ticks carry aren’t released by the tick until 36 – 48 hours or more after the tick starts to bite.

But Lotilaner isn’t approved for use in humans.¹ That may be changing.

Tarsus Pharmaceuticals is developing an oral medication to be taken by humans to provide protection for tick-borne diseases for several weeks at a time. The Irvine, California–based biotech company announced results from a small, early-stage trial showing that 24 hours after taking the drug, it can kill ticks on people, with the effects lasting for up to 30 days. The trial showed tick mortality one day after medication was 97.0% at the trial’s higher dose and 92.0% for the low dose of Lotilaner. Thirty days after medication, tick mortality was 89.0% and 91.0% for the high and low doses. This was a small trial, involving just thirty patients and pathogen-free tick nymphs. A larger scale trial involving folks exposed to wild ticks is in the planning stages.

While antibiotics usually cure Lyme disease, some 5 – 10% of Lyme disease patients suffer prolonged symptoms of debilitating fatigue, body aches, or difficulty thinking following treatment. Many other tick-borne diseases have no treatment. So prevention, in the form of killing ticks before they can infect you, is kind of a big deal.

On the one hand, it’s early in the testing process and none of the research has yet been peer reviewed. On the other hand, it’s been working well in our pets for several years. WC is cautiously optimistic. Of course, there’s the issue of price . . . But let’s not get ahead of ourselves.

¹ Well, technically it is approved for human use as an eye drop to treat blepharitis, or inflammation of the eyelid, a condition caused by tiny mites. That drug, Xdemvy, was approved by the US Food and Drug Administration in July 2023. It stuns and kills mites present in the eyelid.