- Vitamin B6 (pyridoxine) causes neuropathy at intakes of 1000 mg per day or more, which is about 800 times the daily intake from foods. There have also been occasional reports of toxicity at intakes of 100-300 mg per day. The US authorities set the no-observed-adverse-effect-level at 200 mg per day and the safe upper limit at 100 mg per day. A report of neurotoxicity in 2 patients who had taken 24 mg and 40 mg of vitamin B6 per day respectively, may be coincidence rather than a true toxic effect of such relatively low doses. However, physicians need to remain alert to high intakes of vitamin B6 as a cause of unexplained neuropathy.
Ned Tijdschr Geneeskd. 2005;149:2545-6