TL;DR — Plain language summary

There is insufficient evidence to demonstrate valerian root as an effective calming or anxiety relieving supplement, though early evidence for use as a diffuser did not support efficacy.

The science behind it

2 references

Valerian root (Valeriana officinalis) is theorized to alleviate canine stress and modify reactive behaviors primarily by enhancing GABAergic signaling within the central nervous system. The active constituents, such as valerenic acid, are posited to act as mild sedatives by inhibiting the enzyme GABA-transaminase, which is responsible for the breakdown of the inhibitory neurotransmitter GABA. By potentially increasing the synaptic concentration of GABA, valerian root is hypothesized to dampen neuronal excitability and reduce the physiological "noise" associated with fear or hyper-arousal. Additionally, it is suggested that valerian may interact with adenosine receptors to promote a state of relaxation, effectively lowering the dog’s reactive threshold to environmental stressors like thunderstorms or travel without causing the profound sedation seen in clinical anesthetics.

Despite these proposed mechanisms, clinical evidence in dogs remains limited and inconsistent. In randomized observational studies evaluating valerian-based aromatic blends, no significant differences in behavior were identified between the treatment and placebo groups, suggesting that these formulations may not consistently reduce behavioral indicators of stress (Taylor & Madden, 2016). However, recent neurochemical analyses have provided preliminary evidence that oral valerian extract may influence central biomarkers, specifically by decreasing plasma dopamine levels, a shift that could potentially correlate with a reduction in hyper-arousal (Cagin et al., 2025). While these neurophysiological markers are promising, further controlled, placebo-based studies are necessary to establish the clinical relevance of valerian root as a standalone treatment for canine anxiety.

The Bottom Line

The available evidence for use of valerian root in dogs was minimal, thus meaningful conclusions regarding the efficacy, or lack thereof, were unable to be determined. While there is mild evidence of a calming effect in humans, this has not been demonstrated in dogs. Furthermore, the quality of evidence was poor, so further higher quality and large scale studies are required for evidence-based assessment. 

References 2

  1. 1

    Taylor S, Madden J. The Effect of Pet Remedy on the Behaviour of the Domestic Dog (Canis familiaris). Animals (Basel) 2016.

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  2. 2

    Cagin C, Ercan AM, Or ME. Multimodal assessment of Hericium erinaceus and Valeriana officinalis for canine anxiety: Integrating EEG, neurochemical analysis, and behavioral surveys. J Vet Behav 2025.

    View source

Related Reviews

Research Snapshot

2 references on this page
D

Weak

Based primarily on expert opinion, case reports, or "historical use" without controlled testing; multiple negative study results (lack of benefit).

Two small scale studies, dosing unstudied.


Evidence Quantity low
Evidence Quality low
Safety Risk unknown
How we grade evidence
Grade Meaning
A Highly likely/Proven Benefit
B Probable Benefit
C Emerging / Inconclusive
D Weak
F No evidence of benefit, possible harm
n/a Insufficient data
Updated April 8, 2026