Pet Care Blog

Melatonin For Dogs: Uses, Dosage, & Side Effects

Dr. Ricky Walther
Close-up of dog sleeping on the couch

Melatonin is a naturally occurring hormone known to help with a range of health and mood issues in dogs, including Cushing’s disease, anxiety, and more. But what exactly is melatonin? How does it work, and is it safe for dogs?

In this post, we’re discussing everything you need to know about the uses, dosage, and side effects of melatonin supplements in dogs.

Table of Contents:

Pro Tip: Your vet might recommend supplements or prescription food to help your dog with certain health conditions. With pet insurance, you can get reimbursed for a portion of these products so long as they’re used to treat a covered condition.

What is melatonin?

Melatonin is a hormone secreted by the pineal gland, a small gland located above the middle of the brain. The hormone regulates the circadian rhythm of the body, or our biological alarm clock that tells us when we should sleep and when we need to be awake. As the daylight begins to fade and the night gets darker, the brain signals the pineal gland to increase the production of melatonin, which causes us to feel sleepy in response.

That’s why if the production of melatonin in the body drops, sleep problems often develop. This is where melatonin supplements come into play. As a supplement, melatonin may be effective for helping sleep-related issues but it can also help us and our furry friends relax and relieve stress. It can also help with certain medical conditions.

Bottle of pills and reading glasses on table

Is melatonin safe for dogs?

Melatonin is safe for both humans and dogs. However, if your canine companion suffers from a diagnosed medical condition, it’s important to talk to your vet to ensure that melatonin is a safe option.

Uses of melatonin for dogs

More research is necessary but thus far, anecdotal evidence suggests that melatonin can help with sleep and behavioral issues, adrenal disease, as well as non-allergic hair loss in certain breeds of dogs.


As mentioned before, melatonin helps regulate the body’s sleep cycle. People often use melatonin supplements to overcome sleep issues like insomnia and jet lag.

As our canine companions get older, they can start suffering from sleep-related problems. Melatonin supplements can boost your pet’s melatonin levels, making it easier for them to fall asleep, and stay asleep for longer. In addition, melatonin supplements can help regulate the biorhythm of senior pups with cognitive dysfunctions and help them get a better night’s sleep.


Due to its calming effects, melatonin can be effective in soothing pups suffering from anxiety disorders. This includes pets who suffer from general anxiety, separation anxiety, as well as those who have anxious reactions to loud noises, like fireworks and thunderstorms. Melatonin can also help your pup relax before a potentially stressful experience, like a vet visit or a road trip.


Melatonin can be effective in combating seasonal alopecia, also called flank alopecia. In dogs, this condition manifests through bald patches on both sides of the abdomen. It is not clear how melatonin helps flank alopecia but considering the fact that the potential for severe side effects is low, many owners - in consultation with their veterinarian - decide to give it a try.

Melatonin also helps with Alopecia-X, a non-inflammatory disorder that causes hair loss in some dog breeds. There’s no standard treatment for this condition, but many veterinarians report good results using melatonin.

Cushing's Disease

Cushing's disease is a condition in which the adrenal glands overproduce certain hormones, which results in an increase in cortisol levels. Cushing’s can cause a number of side effects including obesity, lack of appetite, insomnia, and hair loss. The conventional medications for this disease in dogs can also cause severe side effects like diarrhea, vomiting, and kidney failure.

In some cases, melatonin can help alleviate some of the symptoms of the disease. If Cushing’s is caused by a tumor on the pituitary or adrenal gland, melatonin will block the uptake of excess cortisol in the body. Because melatonin is much gentler than traditional medication, many veterinarians may recommend it for dogs where traditional medications have resulted in serious side effects.

Melatonin dosage for dogs

Although available over the counter, when it comes to determining the right dosage of melatonin for your dog, you should always consult your vet.

The dosage will depend on whether you’re using melatonin to treat insomnia, anxiety, or another condition, as well as on your dog’s size and weight. Other factors such as pre-existing conditions should also be taken into consideration, but regardless of the dosage size, you should never give your pet melatonin more than three times a day.

Typically, dogs take melatonin orally in the form of tablets, capsules, powder, or liquid, with or without food. If your dog vomits after taking melatonin on an empty stomach, consider administering future doses with food.

If your dog rejects the tablets or capsules, consider placing them inside some peanut butter. If you’re using liquid or powder, you can add it to a treat, but try to make sure your dog consumes the full dosage.

Some vets might recommend giving melatonin via injection, especially if your furry pal is suffering from Alopecia X. Melatonin is also available in the form of subcutaneous implants. These tiny medical devices are inserted beneath the pup’s skin and slowly release melatonin to keep a steady flow through the bloodstream. For pups with Alopecia X, this slow-release form of melatonin is perfect to stimulate hair growth. Each implant works for about four months and should only be inserted by a veterinarian.

Melatonin starts working quickly (about 30 minutes) and its effects last for about eight hours when given in the correct dosage. Therefore, if your dog uses melatonin for sleep, they should receive it shortly before bedtime.

If you miss a dose, give it as soon as you remember, but if it’s almost the time for the next dose, skip the missed dose and return to the regular schedule. Don’t administer two doses of melatonin to dogs in one setting.

An overhead view of a sleeping dog

Side effects of melatonin in dogs

If melatonin is administered properly and at the correct dosage, there shouldn’t be any significant side effects. It should be noted that melatonin has not been approved by the FDA for use in animals and there hasn’t been sufficient research on its safety and side effects. However, if your veterinarian determines that melatonin is a good option for your pet, it may help your pup with a range of issues with minimal (if any) side effects.

Although rare, side effects of melatonin in dogs include:

  • Cramps and tummy upset
  • Confusion
  • Drowsiness
  • Itching
  • Increased heart rate (tachycardia)
  • Fertility changes
  • Digestive upset
  • Insulin resistance in dogs with diabetes

If you notice any of these side effects, be sure to talk to your veterinarian as they might recommend reducing your dog’s dose or suggest a different course of treatment.

To stay on the safe side, make sure to read the labels on melatonin products as some might contain ingredients like xylitol, an artificial sweetener that can be very toxic to dogs.

Melatonin should not be given to dogs who are allergic to it. Melatonin implants should not be used in pregnant dogs and young puppies. The oral form of the supplement should also be used with caution in pregnant and nursing dogs.

Melatonin overdose and allergic reactions are very rare, but if you’re concerned that you have given your pup too much melatonin and they are experiencing adverse side effects, call your vet.

Pro Tip: If your dog requires emergency veterinary treatment, it often comes with a large bill – and that's where pet insurance comes in to help. With a pet insurance policy in place, you’ll know that you have financial support to help you deal with the unexpected expenses, so you can instead focus on getting your pet the care they need.

Possible drug interactions with melatonin

The following drugs can interact poorly with melatonin: warfarin, benzodiazepines, and succinylcholine. Melatonin can make some medical conditions worse and can also decrease estradiol and cortisol levels.

For this reason, it’s important to let your vet know if your canine companion is taking any medications, supplements, or vitamins.

Key Takeaways

  • Melatonin is a naturally occurring hormone produced in the brains of most mammals. People usually use melatonin supplements to help promote healthy sleep, and some veterinarians recommend melatonin for the same purpose for animals.
  • Melatonin also appears to treat many other health issues in dogs, including anxiety, phobias, alopecia, and Cushing’s disease.
  • Although side effects caused by melatonin are rare, they are possible and for that reason, it is always best to discuss the use of melatonin supplements with your veterinarian before giving any to your canine friend.

Do you want to find the best pet insurance?

Let's analyze your pet's breed, age, and location to find the right coverage and the best savings. Ready?

Analyze My Pet

About Pawlicy Advisor

The pet insurance marketplace endorsed by veterinarians, at Pawlicy Advisor we make buying the best pet insurance easier. By comparing personalized coverage and pricing differences we can save you a ton of money, up to 83% in some instances!

Pawlicy Advisor helping a pet parent and their dog find a great deal on insurance

Instantly Compare Pet Insurance Plans

Get Quotes


How Pet Insurance Works

How To Compare Plans

Determine If Pet Insurance Is Worth It

Determine If Wellness Plans Are Worth It

Vet Visit Costs

New Puppy Checklist

Comparison Charts

ASPCA vs. Pets Best

Pets Best vs. Embrace

Embrace vs. Pumpkin

Pumpkin vs. MetLife

More Comparison Charts

Find Your State

New Jersey





New York



More States

Dog Insurance

German Shepherd




English Bulldog

French Bulldog

Great Dane





More Breeds

Ricky Walther, DVM

Dr. Ricky Walther

Ricky Walther, DVM, is a small animal general practitioner in the greater Sacramento, California area. Realizing the positive financial and medical impact that pet insurance can provide for pet parents and the profession, he lends support and advice to companies like Pawlicy Advisor "The Pet Insurance Marketplace") that simplify the process of connecting with veterinary financing resources.

More you might like

Dog lying on bed wrapped in blankets
6 minute read

Distemper in Dogs: Symptoms, Treatment, Prevention

Hand holding pill tablet above dog
7 minute read

Prednisone (Prednisolone) For Dogs: Uses, Dosage, Side Effects

Dog abdomen with bandage from surgery
8 minute read

Pyometra in Dogs: Causes, Symptoms, and Treatment

Dog examined by vet with stethoscope
8 minute read

Heart Murmur in Dogs: Everything You Need to Know

Cat with blue eyes lying on the ground
8 minute read

Pancreatitis in Cats: Causes, Symptoms, & Treatment

Dog in distress with head being held
8 minute read

Addison's Disease in Dogs: Symptoms, Treatment, and Costs

Puppy lying on examination table with IV fluid
6 minute read

Coccidia in Puppies: Symptoms, Diagnosis, Treatment

Cat with ringworm on neck
8 minute read

Ringworm in Cats: Causes, Symptoms & Treatments

Jack Russel with ringworm infection
9 minute read

Ringworm in Dogs: Symptoms, Treatment & Prevention

Dog eating raw meat off cutting board
14 minute read

Can Dogs Eat Raw Meat? Here's Everything You Need to Know

Can reaching onto counter to eat dessert
6 minute read

Can Cats Eat Chocolate?

Dog looking at celery on kitchen counter
9 minute read

Can Dogs Eat Celery? Here's Everything You Need to Know

Dog looking at a carton of eggs
9 minute read

Can Dogs Eat Eggs?

Dog staring at spoon of honey
9 minute read

Can Dogs Eat Honey? Here's Everything You Need to Know

Corgi dog biting an avocado
5 minute read

Can Dogs Eat Avocado? Here's Everything You Need to Know

Beagle dog running with blueberries in mouth
6 minute read

Can Dogs Eat Blueberries? Here's Everything You Need to Know

Basset hound dog staring at peaches with mouth open
6 minute read

Can Dogs Eat Peaches? Here's Everything You Need to Know

Dog walking near tomato plant
7 minute read

Can Dogs Eat Tomatoes? Here's Everything You Need to Know

Dog eating out of bowl on floor
5 minute read

Can Dogs Eat Cashews? Here's Everything You Need to Know

Jack Russel dog swimming in pool toward pineapple
7 minute read

Can Dogs Eat Pineapples? Here's Everything You Need to Know

Golden Retriever pet on head
7 minute read

Carprofen for Dogs: Uses, Effectiveness & Side Effects

Beagle resting head on pillow
10 minute read

Lymphoma in Dogs: Symptoms, Diagnosis, and Treatment

Australian Shepherd puppy with blue eyes
7 minute read

Australian Shepherd Growth & Weight Chart: Everything You Need To Know

Golden Retriever puppy resting on floor
7 minute read

Golden Retriever Growth & Weight Chart: Everything You Need To Know

Shih Tzu puppy
6 minute read

Shih Tzu Growth & Weight Chart: Everything You Need To Know

Beagle dog with corn in mouth
6 minute read

Can Dogs Eat Corn? Here's Everything You Need to Know

Pug lying on the ground looking at cheese
7 minute read

Can Dogs Eat Cheese? Here's Everything You Need to Know

Jack Russel dog grabbing orange from tree
9 minute read

Can Dogs Eat Oranges? Here's Everything You Need to Know

Tapeworm infestation in dogs
6 minute read

Tapeworms in Dogs: Symptoms, Treatment, & Prevention

vet giving medicine orally to dog
7 minute read

Hookworms in Dogs: Symptoms, Treatment & Prevention

Kitten with ear mites
7 minute read

Ear Mites in Cats: Symptoms & Treatment

mixed breed puppy with parvovirus at the veterinary clinic
7 minute read

Parvo in Puppies: Everything You Need to Know

Beagle laying down on the floor
6 minute read

Beagle Growth & Weight Chart: Everything You Need To Know

dog with constipation
8 minute read

Constipation in Dogs: Causes, Symptoms & Treatment

Border Collie dog
6 minute read

Border Collie Growth & Weight Chart: Everything You Need To Know

dog drinking water from river
8 minute read

Giardia in Dogs: Causes, Symptoms, & Treatment

Training a dog on a leash
5 minute read

7 Mistakes People Make When Training Their Dogs

sick cat lying on top of red car
9 minute read

Hyperthyroidism in Cats: Symptoms & Treatment

female veterinarian giving a pill to a brown labrador in a clinic
6 minute read

Metronidazole for Dogs: Uses, Dosage, and Side Effects

Cane Corso dog
8 minute read

Cane Corso Growth & Weight Chart: Everything You Need To Know

Professional veterinarian giving pill to German Shepherd dog in clinic
7 minute read

Trazodone for Dogs: How Does It Work and When Is It Prescribed?

Shiba Inu dog running in field
7 minute read

Shiba Inu Growth & Weight Chart: Everything You Need To Know

Dog waiting to take prescription medication pills
5 minute read

Benadryl for Dogs: Uses, Dosage, and Side Effects

yeast infection in a dog's ear
7 minute read

Yeast Infections in Dogs: Causes, Treatment, and Prevention

Vet holding medications for a little maltese dog
8 minute read

Tramadol for Dogs: Uses, Dosage & Side Effects

sick dog lying on couch
8 minute read

Pancreatitis in Dogs: Causes, Symptoms, Treatment, and Prevention

X-ray of Hip Dysplasia in Dog
7 minute read

Hip Dysplasia in Dogs: Symptoms, Treatment, and Prevention

dog eating a nut
5 minute read

3 Types of Nuts That Are Safe for Dogs to Eat

growing corgi puppies
7 minute read

Corgi Growth & Weight Chart: Everything You Need To Know

poodle puppy playing on the floor
8 minute read

Poodle Growth & Weight Chart: Everything You Need To Know

Back to Blog
A family with pets that are insured by Pawlicy Advisor
Pawlicy Advisor is the leading independent marketplace for finding the best coverage for your pet at the lowest rate.
Join 2,438,795+ insured dogs and cats across the US.
Get a Quote
Our pet insurance partners
ASPCA Pet Health Insurance Logo
Pets Best Pet Insurance Logo
Embrace Pet Insurance Logo
Pumpkin Pet Insurance Logo
MetLife Pet Insurance Logo
Prudent Pet Insurance Logo