[header] How to do a vitamin c flush [title] Speak to your doctor if you have ibs or haemochromatosis. [step] If you have irritable bowel syndrome or an iron deficiency condition like haemochromatosis, talk to your doctor before you do the vitamin c flush. These conditions can get worse if you do the flush without speaking to your doctor first. 
They may recommend a specific dosage of vitamin c based on your condition. [substeps] You should also avoid taking vitamin c if you have kidney issues or if you think you may be allergic to ascorbic acid.