Melatonin Side Effects: What to Know About 5mg & 10mg Doses

Melatonin is a natural hormone and popular sleep aid that helps millions get better rest. However, different dosages can come with various side effects. Let's explore how melatonin works, what side effects to watch for at different doses, and how to use it safely.

What Is Melatonin?

Melatonin is a hormone naturally produced by your body. Its production is suppressed by light during the day and increases in darkness at night, earning it the nickname 'hormone of darkness' or 'sleep hormone.'

Melatonin plays a crucial role in promoting sleep and regulating your circadian rhythm (24-hour cycle). It makes your body feel drowsy and ready for sleep, making it an essential hormone for healthy, restorative rest.

Why Do We Need Melatonin Supplements?

As we age, our bodies naturally produce less melatonin. This decline can make it harder to maintain a healthy circadian rhythm and get quality sleep. That's why many people turn to melatonin supplements.

Recent research is also exploring melatonin's potential for treating various conditions, including breast cancer, headaches, and ADHD symptoms, with promising preliminary results.

Recommended Melatonin Dosage

The optimal melatonin dosage varies based on individual circumstances and goals. For mild insomnia, 1-2mg is often sufficient. Travelers dealing with jet lag or shift workers may need slightly higher doses to maintain their sleep patterns.

Immediate-Release Melatonin

Widely available as an over-the-counter supplement in many countries (though not officially sold in Korea, where people often purchase it from overseas). It works quickly with a shorter duration of effect.

Extended-Release Melatonin

Requires a prescription in Korea. It takes longer to take effect but lasts longer. You may need to take it consistently for several weeks before seeing full benefits.

Special Precautions

•Safety for pregnant or nursing mothers hasn't been sufficiently studied
•May affect growth hormones in children and adolescents
•For severe insomnia, only consider use under medical supervision

Side Effects of 5mg Melatonin

For adults, 5mg or less is considered a standard dose. Melatonin is relatively well-tolerated, so serious side effects at 5mg are uncommon. However, some individuals may experience the following symptoms:

Daytime Drowsiness

You may feel excessively sleepy during the day. This happens when melatonin remains in your system longer than expected.

Headaches and Dizziness

Some people experience headaches or dizziness. If these symptoms persist, consider reducing your dose.

Temporary Mood Changes

Melatonin can cause temporary feelings of depression. If you have a history of depression, be aware that symptoms may worsen after taking melatonin.

Digestive Issues

Mild gastrointestinal symptoms like nausea or stomach discomfort may occur.

If side effects are severe, consider reducing the dose or stopping use and exploring alternative sleep aids. For those with a history of depression, it's recommended to start with 1mg and gradually increase the dose if needed.

Side Effects of 10mg or Higher Doses

Doses of 10mg or higher are considered excessive. The safety of melatonin at 10mg and above is still being studied. Some research suggests it promotes sleep without major concerns, while other studies indicate it may not improve sleep and that safety cannot be guaranteed.

There are two main side effects associated with overdosing. The key is to avoid exceeding 10mg.

Melatonin Hangover

After taking melatonin, you may experience 'hangover' symptoms like headaches, dizziness, and nausea—similar to an alcohol hangover. You might wake up feeling heavy, groggy, and mentally foggy, with these effects lasting throughout the morning.

Insomnia After Discontinuation

When you stop taking melatonin, insomnia symptoms may return. While this might look like addiction, melatonin doesn't cause physical dependence. However, some users develop a psychological pattern where they feel unable to fall asleep without it.

Important Fact

Post-discontinuation insomnia is typically a return of your original sleep issues, not a withdrawal symptom or sign of physical dependence. However, psychological dependence can develop, so caution is advised with long-term use.

Choosing Quality Melatonin Products

According to a 2023 study, 22 out of 25 over-the-counter (OTC) melatonin gummies sold in the United States had inaccurate dosages. This is a serious concern.

When the labeled dose doesn't match the actual content, it can lead to unintentional overdosing or underdosing.

Get a Prescription

For better sleep, it's safer to get a prescription from your doctor rather than buying melatonin overseas. Products approved by Korea's Ministry of Food and Drug Safety guarantee accurate dosing and quality.

Choose Trusted Brands

If buying international products, select those with third-party verification. Look for independent certification marks like USP (United States Pharmacopeia) certification.

Start with Low Doses

If you're new to melatonin, start with a low dose like 1mg and assess how it affects you. Gradually increase the dose if needed.

Timing Matters

Melatonin is most effective when taken 30 minutes to 1 hour before bedtime.

Natural Alternatives to Melatonin

If you're concerned about melatonin side effects or wary of long-term use, try these natural approaches to better sleep.

Light Management

Get plenty of sunlight during the day and reduce blue light exposure at night. This naturally promotes melatonin production.

Consistent Sleep Schedule

Going to bed and waking up at the same time every day helps regulate your body's natural rhythm.

Screen Time Management

Use Good Night Lock to reduce late-night phone use, supporting your body's natural melatonin production.

Relaxation Techniques

Practices like meditation, deep breathing, and gentle stretching can naturally promote better sleep.

Use Melatonin Safely

When used appropriately, melatonin can be a helpful sleep aid. However, different dosages come with different side effects. Even at standard doses of 5mg or less, you may experience drowsiness, headaches, or mood changes. Overdosing at 10mg or more can lead to more serious issues like melatonin hangover or psychological dependence.

The most important things to remember: choose reliable products, start with low doses, and use it short-term rather than long-term. When possible, use prescription products from your doctor, and focus on building natural sleep habits as a fundamental solution.