Have any supplements been studied for postural orthostatic tachycardia syndrome?

There is little to no research on supplements for treating POTS. Some studies have found that people with POTS are at risk for vitamin B12 and vitamin B1 deficiencies^[1], but there haven’t been any studies to determine if supplementing with these vitamins is beneficial. While not studied for POTS specifically, deficiencies in iron and vitamin D are common among patients with chronic fatigue and autonomic dysfunction, and correcting these deficiencies could resolve symptoms.^[2]