There were several questions we didn't have time for on the webcast. Dr. Eagan supplied us with answers:
1. Is there a study on how long trazodone works for a dog? Does its efficacy ever decrease with length of use?
Trazodone is a serotonin antagonist and reuptake inhibitor (SARI) with an onset of effect typically within 30–90 minutes after oral administration. In dogs, the pharmacokinetic elimination half-life averages about 2.8 hours (166 ± 47 min), with high oral bioavailability (~85%) and considerable variability in time to peak plasma concentration (mean = 7.4 ± 4.5 hours; Jay et al., 2013). Plasma concentrations remained within the therapeutic range reported for humans (130 ng/mL to 2 µg/mL) for 4 to 14 hours in most dogs, suggesting a functional duration of action of roughly 4 to 10 hours depending on the individual. Unfortunately, I am not aware of published information examining whether its efficacy decreases over time, but it is often used successfully for longer-term management of anxiety with continued reported benefit.
In shelter contexts, trazodone is usually used as a short-acting situational or transitional medication to help dogs cope with acute stressors such as intake or confinement. The main published shelter study (Abrams et al., 2020) found that administering trazodone during intake was associated with reduced illness, shorter length of stay, and higher adoption rates, supporting its benefit for short-term stress reduction rather than long-term maintenance.
References:
• Jay AR, et al. (2013). Pharmacokinetics, bioavailability, and hemodynamic effects of trazodone after intravenous and oral administration of a single dose to dogs. Am J Vet Res.
• Abrams KM, et al. (2020). Trazodone as a mediator of transitional stress in a shelter environment. J Vet Behav.
2. Once animals are started on medications, are they kept on them for the duration of their stay or only during transition?
In our results (and other studies), shelters reported using medications for both transitions, and for longer term use. Further, in our study, only about 3-4% of respondents said they medicate all animals on intake. If the medication clearly supports ongoing welfare or behavior modification progress, or if progression stops when medication stops, then medication is often continued (e.g., Collins et al 2022)
3. Is there a version of welfare tracking/resources for shelters that use the Five Domains model instead of FAS scoring?
Yes! The ASPCA's Holistic Quality of Life (QOL) Assessment -- part of the Behavior Pathway -- maps closely onto the Five Domains model. It integrates physical health, environment, nutrition, behavior, and mental state, which makes it easy to align with this welfare framework. Other complementary tools include the Animal Welfare Assessment Grid (AWAG) and the Shelter Quality Protocol, which related to the Five Domains model.
https://awag.org.uk/about
https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://www.aspcapro.org/sites/default/files/2024-06/aspca-holistic-quality-of-life.docx&ved=2ahUKEwiI5oGn7pmQAxUsnokEHajdB50QFnoECBwQAQ&usg=AOvVaw27La_hFDT8wSexntYm7wx_
https://www.sciencedirect.com/science/article/abs/pii/S155878782100068X
4. Re 'Causes of behavior problems,' how were developmental issues and genetic factors defined?
In the survey, respondents rated agreement with several predefined statements about causes of behavior problems. 'Developmental issues' referred to experiences during the socialization period (for example, lack of positive exposure to people, animals, or environments). 'Genetic factors' referred more broadly to inherited temperamental traits that may predispose animals to fear or anxiety. Respondents most strongly agreed that the shelter environment itself was the main cause of behavior problems (93%), followed by developmental and underlying anxiety factors.
5. What was the distribution of Canadian shelters across provinces, and were differences between the U.S. and Canada examined?
Canadian shelters represented roughly 28% of the analyzed responses (65 of 233 unique organizations), spanning several provinces. While the study didn't analyze differences at the provincial level, we did compare countries statistically. There were no significant differences between U.S. and Canadian shelters in medication use frequency, comfort, or perceived efficacy. This suggests fairly consistent approaches to psychoactive medication use across North America on a broad level.
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Alison Gibson
Media Projects Manager
Maddie's Fund
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