Melatonin Is Safe for Dogs

Melatonin dosage charts are on supplement packs made for dogs, but we caution you to check with your veterinarian before using melatonin.


Melatonin is safe for dogs and particularly useful in older dogs with some cognitive dysfunction that causes a disruption of the normal sleep-wake cycle. Melatonin also is often used to help with anxiety in dogs, including nighttime anxiety, noise phobias, and separation anxiety.

While you can give the human supplement melatonin to your dog, a safer, simpler route is to use a melatonin product made for dogs. The package’s dog dosage chart will be correct for melatonin levels in that product or, better yet, check with your veterinarian for your dog’s melatonin dosage. My usual melatonin dosage for dogs under 30 lbs. of bodyweight is 3 milligrams (mg) of melatonin twice a day. For dogs 30 pounds and over, I use 6 mg twice a day.

If your older dog is sound asleep all day and up and pacing all night, try keeping him active during the day, preferably out in sunshine, dim the lights two hours before bedtime, and give melatonin right at bedtime. This should help reset your dog’s natural circadian rhythm and help you both get a good night’s sleep.

Melatonin can treat certain types of hair loss. Seasonal flank alopecia usually happens during the winter months when we get less natural light. It occurs most often in Boxers, Bulldogs, Chow Chows, Pomeranians, Poodles, and Alaskan breeds. Your veterinarian will likely suggest giving melatonin two to three times daily for months, until the hair grows back. If your dog suffers from this every year, starting melatonin a couple of months in advance may help prevent hair loss from occurring. If your dog is hard to medicate, ask your veterinarian about Dermatonin, an implant similar to a microchip, which releases melatonin for six months.

Cautions to take before giving your dog melatonin:

  • Melatonin side effects for dogs are usually mild and include drowsiness and gastrointestinal upset.
  • Do not start melatonin without first checking with your veterinarian. Melatonin may interfere with certain medications, like immune-suppressive agents and blood pressure medications. Melatonin is potentially useful in some autoimmune diseases but should not be used in others.
  • Recommended melatonin dosages for dogs vary, so check with your veterinarian.
  • Do not give your dog the melatonin gummies made for humans, as they may contain xylitol, an artificial sweetener that is deadly to dogs. Read all labels and ingredients.
  • Do not use in animals intended for breeding as melatonin may interfere with natural sex hormones.