Can You Give a Dog Melatonin? Here’s What To Know

Brittany Grenus, DVM
By Brittany Grenus, DVM on Aug. 15, 2023
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In This Article

What Is Melatonin?

Melatonin is an over-the-counter supplement that, in recent years, has become popular with humans for its sleep benefits. But what about using melatonin for dogs?

Melatonin can safely be used in dogs at appropriate doses, and it can actually provide several benefits. Research has shown that melatonin is useful for anxiety and stress, sleep, behavioral disorders, and certain skin conditions in dogs. Additionally, there have been anecdotal reports of its use for some autoimmune conditions.

Here’s what to know about melatonin for dogs.

What Is Melatonin?

Melatonin is a hormone normally produced in the pineal gland in the brain. It has been shown to help regulate mood, sleep-wake cycles, and reproduction. The production of melatonin in the body is stimulated by darkness and inhibited by light. This means that both humans and dogs produce melatonin when it gets dark outside and stop producing it when it’s light outside.

The body has specific melatonin receptors, primarily located in the brain. When melatonin connects to these receptors, they become activated and help you—or your dog—fall asleep faster.

Can You Give a Dog Melatonin?

Yes, you can give a dog melatonin, and it’s generally considered extremely safe for them. In the limited studies that have been performed in animals, a toxic dose of melatonin has not been found, meaning a significant amount of the supplement would be needed to cause an overdose.

There are several reasons why you might consider giving melatonin to a dog, including:


Similar to humans, melatonin has been shown to help reduce stress and anxiety in dogs. In fact, it’s even included as part of the “chill protocol,” a specific regimen developed by board-certified veterinary behaviorists to help alleviate fear and discomfort in dogs at the hospital. When using melatonin for stress and anxiety, it should be administered at least one to two hours before the anticipated stressful event.

When using melatonin for stress and anxiety, it should be administered at least one to two hours before the anticipated stressful event.

Hair Loss

Aside from its benefits for anxiety and stress, melatonin for dogs has shown promise in addressing alopecia (hair loss) issues. Melatonin can stimulate the hair cycle and can sometimes be helpful for dogs with specific hair loss conditions, such as alopecia X and seasonal flank alopecia. Consult your veterinarian before starting melatonin treatment for any skin-related problems to ensure the proper dosage and suitability for your dog’s particular needs.

Autoimmune Disorders

Anecdotally, melatonin has shown benefits in certain cases of immune-mediated thrombocytopenia—an autoimmune condition that leads to the destruction of platelets responsible for blood clotting. Again, please consult your veterinarian before starting melatonin treatment for any autoimmune condition.

Melatonin Dosage for Dogs

As with many medications and supplements in veterinary medicine, the appropriate melatonin dosage for a dog depends on the dog’s size and the specific condition being treated. Always consult your veterinarian to determine the best dose for your pet.

How To Give a Dog Melatonin

Melatonin for dogs is given orally and is available in many forms, including tablets, capsules, oral solutions, oral sprays, oral strips, gummies, patches, and tinctures. When choosing a melatonin supplement, there are a few important factors to consider:

  • Read all ingredients on the label. Some melatonin products, especially gummies, may use the artificial sweetener xylitol to make it taste better. However, xylitol is extremely toxic to dogs, so always avoid giving your pup these products.

  • In the U.S., the Food and Drug Administration (FDA) does not regulate over-the-counter supplements as strictly as some other countries do. This can result in a high variability in the quality of the supplement. According to one study of human supplements, as many as 70% of products on the market either lack the listed ingredients or contain contaminants. This is why it’s best to choose supplements that have been tested and verified by a third party, such as the United States Pharmacopeia (USP).

  • Tablets and capsules tend to provide the most consistent dosing and are generally preferred when giving melatonin to dogs.

  • Consider how well your pet takes medication. If your dog is a master at spitting out tablets and capsules, you may want to opt for the liquid form of melatonin.

  • Always consult your veterinarian before giving any new supplements or medications to your dog.

Side Effects of Melatonin for Dogs

There are limited reports of side effects of melatonin in dogs. So when giving melatonin to your dog, monitor them for potential side effects that are sometimes seen in humans. These may include:

If you notice these signs or any other changes in your pet after starting melatonin, contact your veterinarian immediately.

Drug Interactions

While melatonin is generally safe for dogs, it can interact with certain medications. Melatonin has been found to reduce the effectiveness of drugs used to lower blood pressure, such as clonidine, and calcium channel blockers like amlodipine and diltiazem.

Additionally, melatonin can increase the risk of bleeding in pets taking blood thinners such as warfarin. It may also interfere with the effects of corticosteroids and other immunosuppressive drugs.

Again: Talk to your veterinarian before starting your pet on melatonin.

Melatonin for Dogs FAQs

Can you give dogs melatonin for anxiety?

Yes, dogs can take melatonin for anxiety. But if the anxiety is severe enough, your dog may need more than just melatonin to manage anxiety.

How much melatonin can I give my dog?

The appropriate melatonin dosage for dogs depends on a few factors, including the size of the pup and what condition the melatonin is being used to treat. Talk to your vet to get a recommended dosage before giving your dog melatonin.

Will dogs sleep with melatonin?

Yes, melatonin can help dogs sleep better, especially if they experience canine cognitive dysfunction disorder (doggy dementia). This disease often causes anxiety in dogs, especially at night, leading to difficulty sleeping.

Can you give a dog too much melatonin?

Based on the limited current studies, it would be difficult to overdose on melatonin. Even if your dog were to consume an entire bottle, the main concern would be a formation of a ball of pills in the stomach that could get stuck in the intestinal tract.

Can melatonin kill a dog?

There have been no official reports of severe side effects or death in dogs resulting from melatonin use. Still, always consult your vet before giving your dog melatonin or any other supplement.

Featured Image: Adobe/Masson

Brittany Grenus, DVM


Brittany Grenus, DVM


Dr. Brittany Grenus graduated from Tufts Cummings School of Veterinary Medicine in 2018 with her doctorate in veterinary medicine and a...

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