10/24/2026
Going to have to try this!
A 2026 study published in the American Journal of Veterinary Research compared intramuscular (IM) medetomidine with subcutaneous (SC) administration at the governing vessel 20 (GV20/Baihui) acupuncture point in cats.
Researchers randomly assigned 16 healthy cats undergoing elective castration to receive medetomidine at 70 ยตg/kg via either route, with eight cats per group.
What did they find?
โข Faster early sedation: Cats receiving medetomidine at GV20 had significantly higher sedation scores at 5 and 10 minutes post-injection. By 15 minutes, the difference between groups was no longer statistically significant.
โข No significant change in intraocular pressure (IOP): IOP remained comparable between the two groups throughout the 30-minute observation period.
โข Larger pupil diameter: The GV20 group had significantly larger mean pupil diameters than the IM group from 10 to 30 minutes. At 30 minutes, the mean diameter was 9.35 ยฑ 0.98 mm in the GV20 group versus 6.94 ยฑ 1.78 mm in the IM group.
โข Prolonged early recovery: Following atipamezole reversal, cats in the GV20 group had higher recovery scores through 30 minutes, indicating greater residual sedation during early recovery. Scores were comparable between groups at 45 and 60 minutes.
What does this mean for veterinary practice?
Subcutaneous medetomidine administration at GV20 may provide faster early sedation in healthy cats without clinically detectable changes in IOP. However, the associated increase in pupil diameter may be relevant when evaluating ophthalmic patients, and closer monitoring during early recovery is warranted.
Bedir AGB, Yanmaz LE, Akรงora Y, et al. Subcutaneous medetomidine at the governing vessel 20 acupuncture point provides faster early sedation than intramuscular administration without altering intraocular pressure in cats. American Journal of Veterinary Research. 2026. doi:10.2460/ajvr.26.05.0233.