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If your senior dog is becoming more restless at night, you might be looking for solutions to help promote a better night’s sleep for you both. One option worth considering is melatonin — a suitable over-the-counter supplement for dogs. It’s also sometimes administered for dogs with anxiety issues and certain hair loss conditions.
Learn more about when melatonin for dogs could be beneficial and why it’s always best to use it following advice from your veterinarian.
What Is Melatonin for Dogs?
“Melatonin is a natural hormone that regulates sleep cycles,” Dr. Evelyn Galban, Associate Professor of Clinical Neurology and Neurosurgery at the University of Pennsylvania School of Veterinary Medicine, says. All mammals produce this hormone through the pineal gland in the brain. Darkness triggers melatonin production, and the hormone helps regulate the 24-hour cycles of the internal body clock — known as our circadian rhythms.
Melatonin doesn’t just impact sleep-wake cycles. It can also affect a dog’s mood, reproduction functions, and hair growth. The melatonin supplements available for humans and dogs are typically synthetic versions of this naturally occurring hormone.
When to Use Melatonin For Dogs
While melatonin supplements are most commonly associated with promoting a good night’s sleep in humans, studies on their use for dogs are limited. Below, we focus on the possible uses supported by encouraging research.
Sleep Problems
Given melatonin is sometimes referred to as ‘the sleep hormone,’ it makes sense that these supplements are sometimes used to treat dogs experiencing sleep disturbances and associated anxieties, especially those with canine cognitive dysfunction (CCD). “CCD is a condition in older dogs similar to dementia in humans,” Dr. Galban says. “It affects their memory and their behavior, often leading to symptoms like confusion, disorientation, and what can be most disruptive to families: changes in sleep-wake cycles.”
Dr. Galban explains that dogs with CCD might forget their routines, vocalize at night, and get lost and anxious in their home. “Melatonin can have a calming effect, helping dogs rest better and feel more comfortable at night,” she says.
Anxiety
“There are some great published studies that show melatonin, either in combination with other medications or alone, can help to reduce behavioral signs of stress or apprehension in dogs,” Dr. Lena Provoost, Lecturer in Clinical Small Animal Behavior and Welfare at the University of Pennsylvania School of Veterinary Medicine, says.
While the calming properties of melatonin mean this supplement could be a helpful tool for managing a dog’s anxiety, it shouldn’t be viewed as a miracle cure.
Dr. Provoost points out that the mechanism of action (MOA), how the supplement affects the body, is not fully understood, and it’s not clear whether it supports a specific population or all dogs. Plus, the supplement’s effectiveness will depend on how severe the level of anxiety is and in what context it is being used.
Melatonin on its own isn’t a solution for dogs with complex anxiety issues or noise-related phobias. It is typically used as an adjunct within a treatment plan, often alongside other medication and behavior modification advice from professionals.
Hair Loss
“The body’s own melatonin levels can vary with season and time of day—levels are highest during the dark hours and during the winter when the days are shortest,” Dr. Christine Cain, Associate Professor of Dermatology at the University of Pennsylvania School of Veterinary Medicine, says. She explains that higher melatonin levels are associated with a dog’s thicker winter coat growth.
Studies support using melatonin supplements to stimulate hair growth in certain disorders associated with alopecia in dogs or stalled hair growth.
“Alopecia X — otherwise known as hair cycle arrest—is one of these conditions; others include post-clipping alopecia, cyclic or seasonal flank alopecia, and pattern alopecia,” Dr. Cain says. She explains that melatonin may act directly on the hair follicles or on the central nervous system to alter hormone levels.
These types of hair loss disorders in dogs are primarily cosmetic (meaning they affect your dog’s appearance rather than their internal health), and melatonin supplementation is typically a relatively safe and well-tolerated starting point for treatment. Dr. Cain explains that it usually involves a 2- to 3-month trial to measure effectiveness.
How to Administer Melatonin for Dogs
While melatonin is typically considered safe, it’s important to consult with a veterinarian before use. They can determine the correct dose, rule out any serious underlying health issues and offer advice on additional or alternative treatment options.
“We typically have clients purchase oral melatonin supplements over the counter, and they should be aware that, like other over-the-counter supplements (nutraceuticals), these are not FDA-regulated and purity/potency can vary,” Dr. Cain says.
“When purchasing a supplement intended for humans, owners should be careful about the use of a chewable or gummy product that may contain artificial sweeteners that are dangerous for dogs, or using products that contain other components.” For example, some melatonin supplements contain xylitol, and this artificial sweetener is highly toxic to dogs.
Dr. Cain recommends looking for the United States Pharmacopeia (USP) seal on the bottle. This indicates that the quality and components of a dietary supplement have been verified. However, it’s best to check with your veterinarian when in doubt.
“There are also injectable or implant formulations of melatonin available to veterinarians, but these are much less commonly used for dogs than the oral supplements,” Dr Cain says.
Recommended dosages vary depending on the size of the dog and the condition being treated. Again, your veterinarian should advise you on this. For some conditions, such as alopecia, your dog may take two to three tablets per day. For certain phobias, such as fireworks, you might administer fast-acting melatonin a couple of hours before the anticipated stressful event.
What Are the Side Effects of Melatonin for Dogs?
While there has not been much study on the side effects of melatonin for dogs, Dr. Cain says supplementation is typically regarded as being quite safe and well-tolerated. She says that sedation is the main side effect of concern.
Other than feeling a little sleepy, your dog could also get an upset stomach. “I would use caution in recommending this to patients with other gastrointestinal diseases, as it may upset their balance,” Dr. Galban says. Itchiness, an increased heart rate, and confusion are other side effects in humans that may be possible in dogs.
Melatonin can also interact with certain other medications, which is another reason to consult your veterinarian before administering. It may interact with certain immunosuppressives, sedatives, blood pressure and blood-thinning medications, and it isn’t recommended for breeding bitches.
“Some human studies indicate that melatonin can be converted back to serotonin,” Dr. Provoost says. She says you want to be cautious with anxious dogs already taking serotonergic medications. Too much serotonin in the system at any given time can lead to toxicity (serotonin syndrome). In these situations, she says there are likely other drugs that will be more suitable and effective.
This article is intended solely as general guidance, and does not constitute health or other professional advice. Individual situations and applicable laws vary by jurisdiction, and you are encouraged to obtain appropriate advice from qualified professionals in the applicable jurisdictions. We make no representations or warranties concerning any course of action taken by any person following or otherwise using the information offered or provided in this article, including any such information associated with and provided in connection with third-party products, and we will not be liable for any direct, indirect, consequential, special, exemplary or other damages that may result, including but not limited to economic loss, injury, illness or death.