A dog who paces, can't lie still, or seems permanently a little "on," even at home with nothing obviously wrong, is usually dealing with a nervous system stuck in a mildly elevated state rather than any single trigger. It's different from separation anxiety (which is specific to being left alone) and different from noise reactivity (which is specific to a sound). This is more general, and it responds to lowering the overall baseline of arousal rather than treating one particular fear.
What this actually looks like
Circling before lying down repeatedly without settling, getting up again within minutes of finally lying down, panting when it's not hot and there's been no exercise, and a general inability to switch off even during quiet time in a familiar room. Owners often describe it as the dog seeming unable to relax rather than being scared of anything specific.
Why some dogs run hotter than others
Breed, individual temperament, and early life experience all play a role in baseline arousal level, in much the same way some people are naturally more highly strung than others. It's not necessarily a sign that anything is wrong. Under-stimulation (not enough physical or mental exercise for that particular dog) is one of the most common and overlooked contributors, since a dog with pent-up energy and no outlet for it often reads as anxious when the underlying issue is closer to boredom.
Ruling out the obvious first
Sudden-onset restlessness, especially in an older dog, is worth mentioning to a vet, since pain, itching, or discomfort from an unrelated medical issue can look identical to a behavioural inability to settle from the outside. Gradual, longstanding restlessness that's been the dog's baseline for a while is more likely to be temperament or arousal-related than medical.
What actually helps
More structured physical and mental exercise, a consistent daily routine, and a clear "off switch" cue trained deliberately (rewarding calm, settled behaviour on a mat or bed rather than only rewarding excitement) address the behavioural side. On the physiological side, magnesium alongside vitamin B6 has shown a measurable calming effect on markers of stress in human trials, with the combination outperforming magnesium alone (Pouteau et al., 2018; Noah et al., 2021), and L-theanine has shown a calming effect in dogs specifically without sedation (Pike, Horwitz and Lobprise, 2015).
Broono Calm combines L-theanine, passionflower, magnesium, and B6, intended as a daily support for dogs who run at a generally elevated baseline, alongside the behavioural and lifestyle changes above rather than instead of them.
References
- Pouteau, E., Kabir-Ahmadi, M., Noah, L., Mazur, A., Dye, L., Hellhammer, J., Pickering, G. and Dubray, C. (2018) 'Superiority of magnesium and vitamin B6 over magnesium alone on severe stress in healthy adults with low magnesemia: a randomized, single-blind clinical trial', PLOS ONE, 13(12), e0208454.
- Noah, L., Dye, L., Bois De Fer, B., Mazur, A., Pickering, G. and Pouteau, E. (2021) 'Effect of magnesium and vitamin B6 supplementation on mental health and quality of life in stressed healthy adults: post-hoc analysis of a randomised controlled trial', Stress and Health, 37(5), pp. 1000-1009.
- Pike, A.L., Horwitz, D.F. and Lobprise, H. (2015) 'An open-label prospective study of the use of L-theanine (Anxitane) in storm-sensitive client-owned dogs', Journal of Veterinary Behavior, 10(4), pp. 324-331.
