Does the selective serotonin reuptake inhibitor (SSRI) fluoxetine modify canine anxiety related behaviour?



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PICO question

Does administration of the selective serotonin reuptake inhibitor (SSRI) fluoxetine reduce the severity and / or frequency of some anxiety related behaviours in companion dogs, of at least 8 months of age, when compared with no pharmacological treatment?


Clinical bottom line

Category of research question


The number and type of study designs reviewed

Two studies, both randomised, were critically appraised. Each had a placebo control group and the dog's owners were blinded to the treatments

Strength of evidence


Outcomes reported

Both studies provide moderate evidence that fluoxetine, when dispensed at 1–2 mg/kg per day by oral administration and not involving a behavioural modification program for the patient, may reduce some behaviours associated with separation anxiety and / or compulsive disorders. Both studies indicate that a reduction in some unwanted behaviours may be observed after 1 week of fluoxetine medication. Both studies recommend that behavioural and environmental modifications are important adjuncts to pharmacologic treatment of dogs with either compulsive disorders or separation anxiety. Both studies also report that some dogs treated with fluoxetine experienced anorexia / decreased appetite and lethargy, although most of these effects were transient


The clinical recommendation is that fluoxetine at 1–2 mg/kg administered orally, once daily, may be beneficial in reducing the severity of some canine anxiety related behaviours


How to apply this evidence in practice

The application of evidence into practice should take into account multiple factors, not limited to: individual clinical expertise, patient’s circumstances and owners’ values, country, location or clinic where you work, the individual case in front of you, the availability of therapies and resources.

Knowledge Summaries are a resource to help reinforce or inform decision making. They do not override the responsibility or judgement of the practitioner to do what is best for the animal in their care.


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Vol. 7 No. 4 (2022): The fourth issue of 2022

Section: Knowledge Summaries

Categories :  Small Animal  /  Dogs  /  Cats  /  Rabbits  /  Production Animal  /  Cattle  /  Sheep  /  Pig  /  Equine  /  Exotics  /