I've experienced something weird. About a year ago, I took some NAC (600 mg) in the evening (before bed time) just to try it out. I slept really good and was well rested, but I woke up with heart pain and trembling hands and feet (more than usual). Soon after getting up and eating breakfast, I started to get a high level of burning sensation in my head. Recently I chelated about 20 rounds with ALA/DMSA and a few rounds with DMPS. So I decided to try NAC again (again before bed time). The exact same thing happened. How is this possible? I didn't get this feeling while chelating with ALA. Actually the opposite happens. The burning sensation goes down, not up. A burning brain wasn't the only symptom. My anxiety and especially depression went way up. It also made me unease in a lot of (social) situations. The burning became unbearable at a certain moment, and I decided to take a capsule of DMPS (25 mg). The relief was amazing. Almost all my symptoms melted away. I still have a minor burning sensation, but the depression and anxiety are gone. The same is true for the pressure on my heart and the neurological symptoms. I think this is a confirmation that I still have a serious mercury problem. I know that NAC can cross the blood brain barrier and thus has the ability to chelate mercury from the brain. So does ALA. I'm questioning the fact that ALA can actually chelate mercury in an effective way. I feel that it is just acting as a strong antioxidant. Have people tried using NAC instead of ALA for brain chelation?