@rbusch1944 Which formulation are we discussing in your case? If it's the common, and most efficiently uptaken, citrate salt, then 500 mg is obviously too much for your system, and you should advise your physician who prescribed that dose of your experience. If you take 500 mg of bis-glycinate, and it's too much, then maybe you should back off the dose or try yet another salt...malate or taurate maybe? But do run this past the prescribing physician.