Maybe melatonin is your secret to a good night’s sleep, but your dreams involve the zombie apocalypse or showing up to work without pants.
Is it possible your bedtime BFF melatonin is souring your dreams and giving you nightmares?
Does melatonin cause nightmares and weird dreams?
There’s no solid evidence that melatonin supplements cause particularly weird or bad dreams. But, taking melatonin may help you sleep more, which gives you more opportunities to dream or have nightmares.
Taking too much melatonin has also been linked to side effects like nightmares and vivid dreams, but we don’t know the exact cause.
Melatonin is a hormone naturally produced by your body to help you feel sleepy at bedtime. Along with cortisol, it’s a key hormone for your circadian rhythm, which basically runs your sleep-wake cycles, temperature regulation, and metabolism.
Basically, your melatonin levels are influenced by light exposure and your brain makes more melatonin when it gets dark to help you wind down for Zzz’s.
Taking a melatonin supplement close to bedtime seems to kick off sleepy vibes when your own melatonin production is off. This might happen if you’re jet-lagged, work night shifts, or don’t experience “natural” levels of light and darkness throughout the day.
Why do we dream at all? Some think dreams act like a cognitive housekeeper sorting and connecting images from real life, solving problems, packing things away for long-term storage, and taking out the trash.
The truth is, no one really knows the purpose of dreams, much less why we sometimes have really bizarre, vivid dreams.
If you notice you’re having weird, vivid dreams while taking melatonin, here are some possible explanations.
Melatonin improves sleep quality
It’s likely you’re taking melatonin supplements because you don’t sleep well. If melatonin helps your sleep, sleeping more and getting better quality sleep means you have more opportunities to dream.
A 2013 review of 19 studies involving 1,683 people found melatonin especially improved sleep quality, total sleep time, and the time it took to fall asleep for folks with insomnia.
So your wild imaginary nightlife could just be a side effect of getting more Zzz’s.
Melatonin boosts memory processing
When you’re in the rapid eye movement (REM) stage of sleep, the hormone melatonin naturally helps release vasotocin. This substance helps your brain erase memories while you’re dreaming (basically so you can forget that wild dream and avoid confusing it with real life).
REM sleep is also the part of your sleep cycle when you have vivid dreams you’re more likely to remember. And if you take a melatonin supplement, there’s a chance upping the amount of melatonin in your system can increase vasotocin. This may lead to longer stretches of REM sleep, resulting in weird, vivid dreams.
You can take too much melatonin
There’s no official dosage of melatonin that’s considered an “overdose” amount. But, it’s possible to take too much melatonin and get weird, sometimes dangerous side effects.
One side effect linked to taking too much melatonin is nightmares or vivid dreams. But we don’t know exactly why this happens beyond that you have more opportunity for REM sleep and dreaming.
So how do you know you’re taking too much? Research on the melatonin dosage sweet spot varies. Some studies say 0.1 to 10 milligrams (mg) per dose, others say between 1 and 5 mg.
Also because melatonin is considered a dietary supplement, it’s not regulated and tested the same as medications. So, it’s possible the melatonin supplement you’re taking doesn’t contain the ingredients listed or have the dosage of melatonin claimed on the label.
In a 2017 assessment of 30 commercially available melatonin supplements, melatonin content ranged from a fraction of what was claimed on the label to more than 4 times the claimed amount. Yikes!
Nightmares are essentially dreams that cause fear, anger, shame, or sadness. While there’s no research supporting claims that melatonin causes nightmares, there may be some potential connections.
A 2019 review theorizes that nightmares are born from a combo of hyperarousal and the brain’s inability to remove or process fearful thoughts. And you’re more likely to have nightmares if you’re dealing with trauma, anxiety, post-traumatic stress disorder (PTSD), obstructive sleep apnea, or insomnia.
All of these experiences or disorders can also cause trouble sleeping, which could have you reaching for a sleep aid. So, if you take a melatonin supplement, it may unintentionally release suppressed thoughts during REM sleep, further increasing your risk of nightmares.
Taking melatonin is generally considered safe, but there are some side effects to look out for if you take extended-release capsules or higher doses.
Potential side effects can include:
- frequent urination
- stomach discomfort
You may also run into less common side effects like:
- low blood pressure
If you have any side effects, stop taking melatonin and talk with your doctor.
- Melatonin supplements can interact with a lot of prescriptions, over-the-counter meds, and other sleep aids. Keep your doctor in the loop if you want to start taking melatonin.
- Avoid mixing melatonin with alcohol.
- Melatonin can be problematic for people with:
- liver disease
- kidney disease
- autoimmune conditions
- seizure disorders
- There isn’t enough research to support if melatonin is safe for pregnant or breastfeeding peeps.
- There is a risk of allergic reaction.
If you’re convinced melatonin is the cause of your vivid dreams or nightmares, but don’t want to completely cut it out of your routine, try these tips:
- Take melatonin 1 hour before bed. This may help you better relax and destress before you snooze. Plus, it’ll give melatonin time to do its thing before tempting you to reach for more. Just get the A-OK from your doctor first.
- Unwind before you snooze. Meditate, do some yoga, journal, or read your favorite book. Anything that helps your body and brain slow down.
- Keep a dream journal. Write down your dreams and nightmares, keeping track of the nights you took melatonin, and what might have happened during your day to influence your dreams. This can help you assess the connection.
- Try therapy. If you’re dealing with anxiety or trauma. Speaking with a therapist may help you process your feelings and worries that follow you in your sleep.
Melatonin is naturally produced by our brains and helps our bodies wind down for sleep. Some people take melatonin supplements to improve sleep, and it’s considered safe in the short term for most adults.
If you experience disturbing nightmares or vivid dreams while taking melatonin, it’s possible you’re just getting more sleep and upping your chance of having good or bad dreams.