Can I give my dog melatonin? If you’ve been following my three-part series on melatonin, you know the answer is a resounding yes. In Part I, Melatonin for Dogs, we covered melatonin 101—the what and why. In Part II, Melatonin and Canine Cognitive Dysfunction, we discussed using this neurohormone to help senior dogs with sleep-wake disturbances and restlessness associated with doggy dementia. (In fact, melatonin is being studied as a potential treatment for Alzheimer’s disease in humans.)
But it’s worth noting that this mysterious compound can be used to treat other medical conditions in dogs too.
If you are wondering, based on our teaser discussion in Part I of this series, “Can I give my dog melatonin for his skin issues?” or “Can I give my dog melatonin for hair loss?”, you need to keep reading. The vast majority of dermatological conditions in dogs are not responsive to melatonin. However, over my 20+ years as an integrative veterinarian, I’ve seen melatonin work wonders for certain cases.
Can I give my dog melatonin for hair loss?
To answer this question, let’s begin by understanding the role melatonin plays. In addition to improving sleep-wake cycles discussed in Part II of this series, melatonin helps regulate seasonal molting cycles—where animals shed their winter coat in the spring and grow a thick coat in the winter.4
The mechanism by which melatonin is involved in regulating hair growth is not fully understood. However, it is believed that melatonin either works by directly stimulating the hair follicle or by stimulating other hormones within the brain that would affect fur growth.3,4
In dogs, melatonin may be helpful in managing two conditions that cause hair loss: Seasonal Flank Alopecia and Alopecia X. In both cases, the condition is Fconsidered cosmetic—the dog either has a thinner fur coat than normal or the dog has lost fur entirely.
However, there are other diseases where hair loss can occur such as hypothyroidism and Cushing’s disease in dogs. These conditions should both be ruled out and treated if diagnosed.2
Melatonin and Seasonal Flank Alopecia
Seasonal Flank Alopecia is often seen in dogs in northern regions such as the upper Midwest, Northeast, and Canada. Breeds such as Boxers, Bulldogs, Airedale Terriers, Doberman Pinschers, Scottish Terriers, Labrador Retrievers, Giant Schnauzers, and Akitas seem to be predisposed to this condition.2
It is believed that the reduced exposure to light in the winter months may play a role in hair loss.2 Melatonin has been shown to help improve hair coat in some cases, but some cases will resolve on their own during the spring/summer as the daylight hours increase.2,3
Melatonin and Alopecia X
With Alopecia X, the cause of hair loss is still unknown. It is more common in Nordic breeds with double coats including American Eskimo dogs, Chow Chows, Pomeranians, and Alaskan Malamutes.3
Although the exact cause is unknown, it is believed to be related to a hormone imbalance because spaying and neutering intact dogs can cause the hair to regrow.3 In patients that are already spayed and neutered, melatonin is often the first-line treatment because it has fewer side effects than other treatment options.
A success story: Melatonin worked wonders for my patient named Elvis
Elvis was a 4-year-old neutered Pomeranian who, despite having a doting owner who adored him, looked like he’d been rescued from a grooming incident that had gone awry. He had a lovely mane of rust-colored fur around his neck, but his body was bald. Patches of his skin had turned to a blackish leather and his tail looked like that of an opossum with mange.
After checking blood work to rule out other endocrine problems, we diagnosed him with a textbook case of Alopecia X, also known as Pseudo-Cushing’s Syndrome (among other names). We concluded his work up by sending out a sex hormone panel to the vet school at the University of Tennessee. All results pointed away from the “normal” dog endocrine diseases which can cause hair loss—like Cushing’s disease in dogs and hypothyroidism—and toward a diagnosis of Alopecia X.
Marvelous melatonin to the rescue
We started Elvis on oral melatonin. I explained to the owner that we would commit to a 3-month trial before making any further changes. Dogs with Alopecia X reportedly demonstrate hair regrowth in 40-60% of the cases.
It took over four months until Elvis had the coat of a normal Pomeranian, but he regrew his hair! It was somewhat stunning to behold.
We don’t fully understand how melatonin works for these dogs, but it might have a direct influence on the hair follicles. Incidentally, we stopped the melatonin after Elvis’s coat was near perfect and just monitored for recurrence.
It’s also worth noting that many veterinary dermatologists prefer a brand of melatonin called Nature’s Bounty for best results. I truly can’t say if this recommendation has merit, but it was indeed the brand we used with Elvis.
Melatonin and platelet restoration: Mind-blowing results
In dogs and humans, there is a condition known as Immune Mediated Thrombocytopenia (IMT), where the body attacks and destroys its own platelets. Platelets are blood cells that are critically important to stop bleeding. So when their numbers get too low, the patient can experience severe bruising and bleeding.
A recent study in humans diagnosed with difficult to control IMT showed improved ability to clot and stop bleeding when melatonin was added to their treatment protocol.1 It is believed that melatonin helps IMT patients by encouraging the cell that produces platelets in the bone marrow, megakaryocytes, to divide more quickly.1,4,5 In other words, melatonin appears to stimulate platelet production in immune-mediated thrombocytopenia. This is mind-blowing to me!
Melatonin and other medical conditions
There may be benefits of using melatonin, in combination with other treatments, for management of certain cancers. There have been some studies that indicate that melatonin may have antioxidant properties to counteract the effects of chemotherapy and it may help prevent the spread of certain types of cancer.6,8
Other studies indicated that melatonin may sensitize some cancers to chemotherapy, allowing for treatment of some resistant tumors.7 In mice, melatonin helped improve anemia caused by chemotherapy medications.1
Using melatonin as an additional therapy for seizures has received mixed reviews. There is some evidence that in dogs who had a high number of nighttime seizures, melatonin helped reduce the number of seizures.3
However, in humans, melatonin increased the risk of seizures.5,6 Therefore, it is important to talk with your veterinarian or veterinary neurologist if your dog has seizures and you’d like to learn more about melatonin for this condition.
Can I give my dog melatonin supplements? Beware of formulations that include xylitol
While I mentioned the dangers of xylitol in Part I of this series on melatonin, it’s important to reiterate it here too.
It is critical that dog owners avoid formulations of melatonin that contain xylitol. While melatonin itself is very safe, xylitol is HIGHLY toxic to dogs. For more information about the dangers of xylitol, please read my article: Xylitol and Dogs: Why Your Dog’s Counting on You to Read This.
Also, if your vet feels that your dog is a good candidate for melatonin supplements, he or she will recommend the correct dosage.
Speak with your veterinarian about giving your dog melatonin
Finally, we have just touched the tip of the iceberg on all that this amazing neurohormone can accomplish. As our knowledge of melatonin grows, we will likely see it become used more frequently to aid in treating a variety of conditions with very minimal side effects. Remember to talk with your veterinarian before starting any additional medications or supplements.
What questions do you have about melatonin?
Please comment below. We can all learn from each other.
- Byers, C G. “Just Ask the Expert: Is There a Role for Melatonin in Dogs and Cats with IMHA?” DVM360, 27 July 2017, veterinarymedicine.dvm360.com/just-ask-expert-there-role-melatonin-dogs-and-cats-with-imha.
- Jeromin, A M. “Seasonal Affective Disorder Can Be Culprit for Canine Hair Loss.” DVM360, 1 Apr. 2003, veterinarynews.dvm360.com/seasonal-affective-disorder-can-be-culprit-canine-hair-loss.
- “Melatonin and Seasonal Alopecias.” Veterinary Practice, 1 Nov. 2013, veterinary-practice.com/article/melatonin-and-seasonal-alopecias.
- “Melatonin.” Plumb’s Veterinary Drug Handbook, Veterinary Information Networm, 1 Jan. 2015, www.vin.com/members/cms/project/defaultadv1.aspx?id=4692338&pid=451&.
- “Melatonin.” VIN Veterinary Drug Handbook, Veterinary Information Networm, 30 June 2017, www.vin.com/members/cms/project/defaultadv1.aspx?pId=13468&id=7868548.
- “Melatonin: Side Effects, Uses, Dosage (Kids/Adults).” Edited by L Anderson, Drugs.com, 26 Mar. 2019, www.drugs.com/melatonin.html.
- Reiter, R J, et al. “Melatonin, a Full Service Anti-Cancer Agent: Inhibition of Initiation, Progression and Metastasis.” Int J Mol Sci, vol. 18, no. 4, 2017, doi:10.3390.