Apple Cider Vinegar Drug Interactions
Combining insulin with apple cider vinegar could increase the risk of low blood potassium. Again, this is probably just an issue when apple cider vinegar is used in large amounts.
Check with your healthcare provider before taking apple cider vinegar with any diuretics, as this may cause a decrease in blood potassium levels. Small amounts of apple cider vinegar used in cooking will likely not cause any problems.