Actually, there's all sorts of documentation on the net of it being used at 800mg doses in clinical trials, and few adverse effects were found, but even fewer are found when you use it just once and not daily for months. This stuff is decently tested as far as drugs go, and I haven't noticed any side effects from it personally. Recommended dosages are typically very low to prevent drug companies from being sued when someone accidentally ODs or has a bad reaction. There's pretty much nothing OTC you can't take 4x the recommended dose of and not be fine. Take four Tylenol and nothing bad's gonna happen, and it's the same with Aspirin, Benadryl...nearly all OTC medications. Not to say that it's safe to pop pills just because they're OTC, but in general, they're pretty safe. Most drugs that are available OTC are available as a prescription as well, and typically the only difference is that the prescribed dose is 2-4x as much as the OTC dose. Sorry for my rambling, I'm kinda out of it.