My Dog Ate Melatonin! Measly Mistake- Or Menace?

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After a long, stressful day of work, taking some melatonin supplements seems like a great way to help you unwind and get some much-needed sleep.

However, as you enter your bedroom, you spot your bottle of melatonin open on the floor- empty except for a lone silica packet.

Your mind jumps immediately to the worst-case scenario; one that involves your furry friend currently wagging its tail nonchalantly next to you.

“Oh no, my dog ate melatonin! What’s going to happen?!”

Although you might be worried, eating melatonin medications or supplements generally will not cause any problems for your dog. The exception is if it contains xylitol, which can be very toxic to your dog.

Melatonin can be effective in relaxing your dog and can sometimes even be prescribed as a sleep aid. When melatonin is administered correctly, it may provide temporary relief for various medical conditions such as separation anxiety, insomnia, Cushing’s disease and hair loss.

However, whether or not melatonin is recommended for your dog is dependent on its specific situation, so talk to your vet about the best course of action.

The effects of Melatonin generally can last for around 8 hours (or one sleep cycle). However, the exact efficacy will depend on the dosage, and on how your dog’s body reacts to the hormone.

In cases of melatonin overdose or xylitol poisoning, you will need to contact your vet immediately as there can be severe consequences.

What Is Melatonin, Anyway?

Melatonin is a naturally occurring hormone that the body produces via the pineal gland. It is responsible for regulating the sleep-wake cycle, and plays a key role in keeping an animal’s circadian rhythm humming along smoothly.

Melatonin was first discovered as an antioxidant in 1993, and a patent for its use as a sleep supplement was filed in 1995. As a popular sleep aid, it is usually taken orally for temporary bouts of insomnia that result from situations such as shift work or jet lag.

While the actual results for treating insomnia are mixed, it does appear to allow the taker to fall asleep faster– though with no noticeable beneficial effect on total sleep time. It has also been shown to be ineffective for treatment of cognitive dysfunctions such as dementia or Alzheimer’s.

Generally, melatonin is very safe as a dietary supplement and is sold over-the-counter in Canada and the United States. There are minimal side effects when used by humans at low doses, and these can include:

  • Sleepiness
  • Nausea
  • Diarrhea
  • Lethargy
  • Dizziness
  • Tiredness
  • Mood swings.

What Would Happen If A Dog Ate Melatonin?

Pile of white pills in blister packs

The symptoms that your dog may experience will be slightly different depending on whether it ate melatonin with, or without, xylitol content. Pure melatonin will typically begin to take effect after around 20 minutes following ingestion.

The primary effect of melatonin (without xylitol) involves sleepiness. The dog will appear lethargic, and some initial consequences may include a faster heart rate and GI issues such as stomach pain and diarrhea.

The severity of side effects that can result from consuming melatonin will depend on the dosage, and your dog’s individual sensitivity to melatonin. Other side effects may include loss of coordination and itching.

If a diabetic dog eats a relatively large amount of melatonin, or consistently consumes it over a prolonged period of time, insulin resistance may result. Melatonin overconsumption may also influence a female dog’s reproductive cycle.

Generally, your dog should naturally remove excess melatonin from their body after around 24 hours.

So far, there has been no significant evidence to suggest that melatonin (without the presence of xylitol) can cause any potentially harmful complications.

Under What Circumstances Should You Be Extra Careful With Melatonin Around Dogs?

Melatonin should not be given to dogs if they are:

Pregnant– Melatonin may affect fetal development

Very Young (Below 12 weeks of Age)

Taking Other Medications– Certain medications can interact with melatonin and lead to complex issues. An example is if your dog takes aspirin and melatonin concurrently, which can significantly impair blood clotting.

Melatonin should also not be administered if your dog is suffering from:

Liver Problems– Melatonin is broken down in the liver. Any abnormal interaction with melatonin may lead to complications.

Brain Complications– Melatonin primarily affects the brain. Irregular cranial behaviour may lead to incorrect processing of melatonin and lead to downstream effects.

Bleeding Issues– Melatonin slows blood clotting, which can lead to excessive bleeding from wounds or internally.

Seizures– Whilst inconclusive, ingesting melatonin may increase the intensity and occurrence of seizures.

Hypersensitivity or Allergy to Melatonin

For a more comprehensive understanding of when consuming melatonin can be bad for your dog, contact your vet for additional advice.

What Happens if My Dog Ate Melatonin with Xylitol?

Vet examining dog on table

It is a more severe issue if your dog has consumed melatonin that has been combined with xylitol. In addition to the effects as discussed in the previous section, xylitol can cause potentially lethal complications.

Xylitol is toxic to dogs, and it can lead to a significant decrease in blood glucose levels and cause liver damage. However, some dogs may only show symptoms of liver injury and not symptoms of low blood glucose levels.

Initial symptoms of xylitol poisoning include vomiting and weakness.

Some delayed signs of xylitol poisoning include drowsiness and loss of coordination and in extreme cases can lead to seizures, coma and death. Death can be caused by complete liver failure, internal bleeding and impaired blood clotting.

The effects of xylitol can begin between 15 minutes to 12 hours after consumption. The effects can last for at least 12 hours.

It only takes around 50 milligrams per pound of body weight to begin to see relatively severe symptoms of xylitol poisoning.

What Should You Do if Your Dog Ate Melatonin with Xylitol?

If your dog has ingested melatonin containing xylitol, you will need to contact your vet immediately. They may ask you to induce vomiting using 3% hydrogen peroxide.

The toxic effects of xylitol can take effect very quickly, so it is imperative you act quickly.

It is important you note down the time at which they had taken the medication, the amount of melatonin they have ingested and if possible, the xylitol quantity.

Your dog is likely to be hospitalized for approximately 24 hours to ensure the xylitol has been completely removed from their body.

The veterinary hospital will induce vomiting and provide your dog with IV fluids, test their blood for glucose levels and provide medications to help with symptoms and remove xylitol.

“My Dog Ate A Whole Bottle Of Melatonin”… How Much Melatonin Is Too Much For A Dog?

White pills in white bottle

The appropriate dosage of melatonin will be influenced by your dog’s size, age and how sensitive it is to melatonin. You will be able to obtain an accurate dosage of melatonin and other products like coconut oil by contacting your vet.

Anecdotally, you can provide melatonin according to the following guidelines:

Small Dogs (Approx. Less than 10 pounds): 1 milligram of Melatonin

Medium Dogs (Approx. around 30 pounds): 3 milligrams of Melatonin

Large Dogs (Approx. around 60 pounds): 6 milligrams of Melatonin

Maximum Melatonin dosage each time is roughly around 1 milligram per 10 pounds of bodyweight.

Try not to provide melatonin more than three times a day. Excess melatonin in a day may disrupt a dog’s sleep-wake cycle.

If your dog ate xylitol-free melatonin according to these dosage guidelines, it is unlikely your dog will suffer from any complications.

Can Dogs Overdose on Melatonin?

While dogs can technically overdose on melatonin, it is unlikely to lead to death.

Some mild symptoms of melatonin overdose include lethargy and stomach issues such as diarrhea.

In severe cases of overdose, your dog will likely appear confused, begin vomiting, have a very high blood pressure and experience seizures.

If your dog has overdosed on melatonin, it would be best to consult with your vet immediately. You can also contact the animal poison control helpline such as ASPCA- (888) 426-4435 for advice.

Can Melatonin Kill Your Dog?

Two white pills and pill bottle

If your dog ingests melatonin in moderate quantities and the melatonin does not contain xylitol, it should not kill your dog.

Even if your dog has consumed a large quantity (for example, a whole bottle), it is unlikely to lead to death. However, in situations such as these, it is best that they receive immediate medical attention.

If the melatonin your dog has ingested contains xylitol (which you can find out from the container, asking the provider or contacting a vet), then yes, consuming melatonin with xylitol can lead to death.

Prevention of Melatonin Overdose

To prevent your dog from overdosing, here are a few steps you can take:

– Always keep melatonin out of your dog’s reach

– Consult with a vet for the appropriate dosage and administration method

– Note down the date, time and amount of melatonin that your dog ingested

– Ensure people who provide melatonin to your dog know how much it has taken already to prevent an overdose.

These steps can be applied for any other medications or supplements like collagen to prevent an accidental overdose.

In Summary

It is generally considered safe if your dog ate melatonin in small quantities, as some vets even use it as a medication for helping with anxiety and insomnia.

However, it is possible that if your dog ingests a whole bottle of melatonin it can suffer from an overdose.

The greatest danger of melatonin is not melatonin itself, but the xylitol that may be mixed into the formulation.

Consulting with your vet if your dog has eaten a large quantity of melatonin or melatonin with xylitol is the safest option.

Ensure you keep melatonin out of your dog’s reach at all times, in case it leads to a costly mistake.

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