The first time I took melatonin, I took 1mg the first night and fell asleep fairly quickly. The next night I had to take 3mg. Now, months later, I'm up to 25mgs a night. It's after 4 in the morning and I'm wide awake. I want to take 10 or 15 more mgs. All I have are 5mg tablets and I know one of them isn't going to be enough. I'm not trying to kill myself, I just want to make sure I'm out for the night. I don't have a Dr. or medical insurance, so I'm stuck with melatonin. So my question is, would it be safe to take more 4 hours later? And how much would be ok?