PubMed Vijayvargiya P, Camilleri M, Shin A, Saenger A
Clinical indications include deficiency due to inadequate diet or malabsorption, drug-induced deficiency (for example, from long-term isoniazid or oral contraceptives), and certain inborn errors of metabolism (such as pyridoxine-dependent seizures or sideroblastic anemia)
Although a fairly large proportion of patients have reported a number of side effects, particularly at the gastrointestinal level (nausea, vomiting, diarrhoea), these side effects tend to diminish over time and adherence to treatment remains high, with about 5% of patients discontinuing treatment due to side effects
Both Ruhoy and Kaufman appear to have glommed onto these drugs via the 700-plus doctors MASTERMINDS network of health providers in communication with each other about ME/CFS, FM, MCAS, POTS, long COVID, etc