You wouldn't be likely to die or anything but it still isn't good if the bottle doesn't list it as a safe dosage. The body naturally makes melatonin and that causes people to think it's safe. Sometimes too much of a good thing can be harmful.
Instead of taking the pills together, try to space them out a little while so the body becomes sleepy. It is suggested to buy some lower dose ones and take them nearing the end of the day to help you relax and get ready for bed so that when you lay down you can actually sleep without needing higher dosages.
You can still become reliant on these sorts of things to fall asleep. If your body sees that you're getting "enough" from an outside source then it won't produce enough when you actually need it. Try to do things that are relaxing near the end of you day. When you begin your day remember to burn off some energy. [ Peeps's advice column | Ask Peeps A Question ]
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