FDA alert warns of possible accidental overdose with anti-noise aversion drug

Published on May 23, 2017

tech_smVeterinarians prescribing the drug Sileo to treat noise aversion in dogs should take care to educate pet owners about how to operate the drug’s oral syringe properly, so as to guard against accidental overdoses, according to an alert issued Tuesday by the U.S. Food and Drug Administration (FDA).

Sileo, a gel that is given to dogs by mouth, includes an oral dosing syringe with a ring-stop mechanism on the plunger that must be dialed and locked into place to set the correct dose for each dog. “The FDA has received 28 reports involving Sileo overdoses in dogs due to the (syringe’s) ring-stop mechanism not properly locking at the intended dose,” according to the alert. No deaths have been reported.

“All prescribing veterinarians and users should be aware of the possibility for accidental overdose” if the syringe is not properly locked, the FDA said. “Veterinary staffs are strongly encouraged to provide education in proper operation of the syringe to dog owners before dispensing the drug. Dog owners should be aware of potential signs of overdose, and they should contact their veterinarian if their dog exhibits any of these signs.”

According to the FDA alert, clinical signs of overdose include lethargy, sedation, sleepiness, slow heart rate, loss of consciousness, shallow or slow breathing, trouble breathing, impaired balance or incoordination, low blood pressure, and muscle tremors.

Zoetis, in a written statement received by the AVMA late Tuesday, acknowledged rare reports of accidental overdoses resulting from “improper administration (failure to securely lock the ring-stop) by the pet owner. In those cases, clinical effects were temporary. We at Zoetis take these reports seriously.  The health and well-being of animals is our highest priority.”

“As with any prescription medication, it is important for pet owners to fully review the instructions to ensure proper administration to a pet,” Zoetis said. “We encourage veterinarians to discuss with pet owners how to use the syringe and administer Sileo. We also encourage pet owners to review the step-by-step dosing instructions that are included in the Sileo package and the instructional videos available online on the Sileo product website (www.sileodogus.com).”  Corresponding veterinary resources are available at Sileodvmus.com.