#9-Dogs with Severe Aggression in Vet Clinic

NMVMA listserve Veterinary Behavior Tip #9

Jeff Nichol, DVM
Behavior resident in private practice training
Veterinary Emergency and Specialty Centers

Albuquerque and Santa Fe Dogs with Severe Aggression in the Veterinary Clinic

There are dogs so intensely reactive that no amount of low-stress handling will help. You can rally the troops for a high-risk/high-stress canine rodeo or you can apply the power of modern medicine aka chemical restraint. Options include prescribing anxiolytics to be given at-home prior to the visit or having your client administer sedation by the oral transmucosal (OTM) route.

Premedicate at home:

  • Oral trazodone (5 to 7 mg/kg) + oral lorazepam (0.1-0.2 mg/kg) given 1-2 hours before leaving home for the veterinary clinic.
  • Gabapentin (8-20 mg/kg) can be added.
  • At-home trials are advised.

At the veterinary clinic:

Sedation by the oral transmucosal (OTM) route is well worth considering. Our arsenal of injectable sedatives and anxiolytics can be safely administered by dog owners into the corner of their dog’s mouth while we and our staff are out of sight and out of mind. Here are some cocktails that can avoid the struggles that condition our patients to become increasingly hostile with successive veterinary visits.

OTM Anxiolytic:

  • The typical IM dose of dexmedetomidine provides equivalent sedation1
    • Detomidine (Dormosedan) gel at 0.35 mg/m2 is an anxiolytic dose.
    • Time to effect is 45 minutes (maybe up to 60 minutes).
    • Duration of maximal effect was approximately 30 minutes, but subtle effects lasted longer.

OTM deep sedation:

  • Acepromazine (1.5 mg/kg) + butorphanol (0.4 mg/kg) + detomidine transmucosal gel (8 mg/m2) 1 hour prior to the appointment.
    • Can use Dexdomitor injectable instead of detomidine gel + butorphanol at the normal IM dosages (Dexdomitor dose 375 – 500 micrograms/m2 body surface area).
    • Laterally recumbent and quiet in the car but still awake and sensitive to noises at lower dosage; deeper sedation at higher dosage. 

For euthanasia of aggressive dogs:

  • Start with above OTM sedation.
  • Can follow with Telazol 10 mg/kg IM
    • Telazol comes as a powder.  Instead of using sterile water you can reconstitute with butorphanol injectable solution at the above dose.
    • Ten minutes later the dog should be deep enough to move into the clinic, place an IV catheter, and euthanize.
    • Blood pressure will be low, so placing the catheter may be challenging.


  • Acepromazine – doses in Plumb 0.55 – 2.2 mg/kg orally.
    • Use as a sole oral sedative is questionable at best. It is poorly absorbed when given with food.
    • Many dogs appear relaxed, but can easily overcome their sedation with any stimulus, leading to unpredictable behavior. Or, even worse, leading to a false sense of security on the part of the staff or veterinarians with the potential consequence of injury.
  • Diazepam (Valium)
    • Dose up to 2.2 mg/kg orally.
    • Can have a disinhibitory effect on certain patients.
    • Removing what little inhibition the patient may have to bite you is less than ideal.
  • Alprazolam (Xanax)
    • 0.1mg/kg for anxiety orally.
    • Anecdotally, some veterinarians are giving this at 0.5mg/kg up to 8mg total dose for oral sedation in the extreme case.
    • May also disinhibit aggression.
  • Telazol & Acepromazine2
    • Telazol powder at 20mg/kg mixed in food.
    • Telazol had predictable, heavy sedation when combined with 2.2mg/kg acepromazine PO.
      • 7 of 8 dogs were sternally recumbent and reluctant to stand.
      • 6 of 8 dogs were laterally recumbent and unable to maintain sternal recumbency.
      • The patient may need to be kept in the hospital until able to ambulate.
  • Other Combinations:
    • Acepromazine (1.25mg/kg) + Diazepam (0.5mg/kg) orally
    • Phenobarbital (2mg/kg) + Diazepam (1mg/kg) orally

I have found clients amenable to paying for gentle (deep) sedation when the hazards of high-stress encounters are explained. I hope this helps keep everybody at your place relaxed and safe.

All the best,
Jeff Nichol, DVM

1 The Use of Oral Transmucosal Detomidine hydrochloride Gel to Facilitate Handling in Dogs
Hopfensperger, Messenger, Papich, et al

2 Comparison of Five Regimens for Oral Administration of Medication to Induce Sedation in Dogs Prior to Euthanasia
J Am Vet Med Assoc 213[2]: 240-242 Jul 15’98 Prospective Clinical Study 9 Refs
Edward C. Ramsay, DVM, and Randolph W. Wetzel, BS
Department of Comparative Medicine, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37901-1071