Comparison of five regimens for oral administration of medication to induce sedation in dogs prior to euthanasia.

OBJECTIVE

To compare regimens for oral administration of medication to induce sedation in dogs prior to euthanasia.

DESIGN

Prospective randomized clinical study.

ANIMALS

37 dogs.

PROCEDURE

Groups and medications were as follows: group 1, acepromazine (n = 8); group 2, tiletamine-zolazepam (8); group 3, tiletamine-zolazepam and acepromazine (8); group 4, tiletamine-zolazepam and butorphanol (6); and group 5, pentobarbital sodium (7). Capsules or tablets were placed in each dog's food. Sedation was scored at 3-minute intervals after consumption of medication for at least 60 minutes. Dogs with signs of persistent or progressive sedation were observed for 90 minutes.

RESULTS

Only 2 dogs in group 1 became slightly ataxic. All group-2 dogs were slightly ataxic, and 4 of 8 became laterally recumbent (mean time to lateral recumbency, 62 minutes). Seven of 8 group-3 dogs became sternally recumbent, and 6 of these dogs became laterally recumbent (mean, 48.6 minutes). Four of 6 group-4 dogs were slightly or moderately ataxic, and 1 of these dogs became laterally recumbent (mean, 48 minutes). One dog in group 5 was not affected by the medication, but all other group-5 dogs became laterally recumbent (mean, 59 minutes).

CLINICAL IMPLICATIONS

Of the medications evaluated, tiletamine-zolazepam and acepromazine at dosages of approximately 20 mg/kg (9.1 mg/lb) and 2 mg/kg (0.91 mg/lb), respectively, or pentobarbital sodium alone (63.2 +/- 5.1 mg/kg [28.7 +/- 2.3 mg/lb]) most consistently induced profound sedation and lateral recumbency after oral administration to dogs.