Table 4:

B vitamins and possible clinical uses

Vitamin	Clinical uses	Suggested regimen
Thiamine (B1)	–Wernicke-Korsakoff syndrome treatment	–The European Federation of Neurological Societies: Thiamine 200 mg IV 3 times daily until improvement stops 3,24 –The Royal College of Physicians: Thiamine 500 mg IV 3 times daily for 3 d to be followed with 250 mg IV or IM once daily for 5 d or until clinical improvement stops –Thiamine should be given before any carbohydrates 15,25
	–Alcoholism/Clinical Institute Withdrawal Assessment for Alcohol (CIWA) protocol 15	–Thiamine 100 mg IV once daily for 3–5 d2
	–Bariatric surgery 15	–Thiamine 100 mg IV for 7–14 d in mild deficiency –Thiamine 500 mg/d IV for 3–5 d followed by 250 mg/d for 3–5 d or until symptoms resolve followed by 100 mg/d orally indefinitely in severe deficiency 15
Riboflavin (B2)	–To treat stomatitis, cheilitis, and glossitis 24 –Cataract prevention 4 –Migraine prophylaxis 24	–0.5 mg/kg orally daily until symptoms resolve –400 mg daily for 5–6 y 4 –400 mg daily for a minimum of 3 mo (evidence level B) 24
Niacin (B3)	–To treat pellagra 6,7	–Nicotinamide 100 mg every 6 h orally until resolution of acute major symptoms 6,7
Pantothenic acid (B5)	–Acne, anxiety, allergies, rheumatoid arthritis 8,26 –Accelerate wound healing, lowers triglyceride levels 8,17,26 (Small studies)	–5 mg orally daily 2,8
Pyridoxine, pyridoxal, pyridoxamine (B6)	–INH overdose-related seizure or toxic INH dose without seizure 19,20	–Pyridoxine dose should be equivalent to the maximum suspected amount of ingested isoniazid. If ingested isoniazid is unknown, 5 g of pyridoxine should be given IV at a rate of 0.5–1 g/min pending seizures to discontinue or maximum dose given 19,20
	–Ethylene glycol overdose 20	–50–100 mg IV every 6 h 20
	–Nausea and vomiting of pregnancy 27	–10–25 mg orally every 8 h (evidence rating A) 27
	–Premenstrual syndrome 28	–50–100 mg daily (limited evidence) 28
Biotin (B7)	–Inherited enzyme deficiency 12 –Brittle hair syndrome 12	–10,000–30,000 μg/d orally 29 –300–3000 μg/d (low-quality evidence) 12
Folic acid, folate (B9)	–Megaloblastic anemia 30 –Pregnancy –Dialysis and malabsorption –Hemolysis 30 –High risk for neural tube defects 30	–1–5 mg orally once daily for 4 mo or until term in pregnancy 30 –0.4–0.8 mg/d (Grade A) –5 mg orally once daily 30 –1 mg orally daily –4 mg orally daily 30
Cobalamin (B12)	–B12 deficiency maintenance dose –Megaloblastic anemia/B12 deficiency without neurologic symptoms 14,30 –In symptomatic anemia, neurologic symptoms, or pregnancy 14,29,30 –Bariatric surgery 31 –Concurrent folate and B12 deficiency 31	–1000 mcg IM monthly or 1000–2000 mcg orally daily until deficiency is corrected 14,30 –1000 mcg IM 3 times weekly for 2 wk 14,29–31 –1000 mcg IM every other day for 3 wk followed by 1000 mcg patently once monthly 14,29,30 –1000 mcg orally daily indefinitely 31 –B12 should be replaced first 31

IM, Intramuscularly; INH, brand name of isoniazid.; IV, intravenously.