B Vitamins and Iron

Question 1

What is the role of Vitamin B1 (Thiamine)?

Answer 1

Vitamin B1 (Thiamine) plays a role in the synthesis of nerve-regulating substances and is essential for the metabolism of carbohydrates.

Question 2

What conditions are indicated for Vitamin B1 supplementation?

Answer 2

Vitamin B1 supplementation is indicated for the prophylaxis of B1 deficiency, Beriberi, and Wernicke’s encephalopathy.

Question 3

Which patients are at higher risk for Vitamin B1 deficiency?

Answer 3

Alcoholics are at higher risk for Vitamin B1 deficiency.

And malnourished patients too

Question 4

What are the consequences of Vitamin B1 deficiency?

Answer 4

Vitamin B1 deficiency can lead to brain damage in regions such as the thalamus, midbrain, and brain stem, manifesting as Wernicke-Korsakoff syndrome (a condition commonly associated with alcoholism)

Can cause visual disturbances
Ataxia (Specific loss of muscle coordination)
Tremors
Impaired memory and confusion

Question 5

How is Vitamin B1 absorbed and excreted?

Answer 5

Vitamin B1 is absorbed in the small intestine

Stored in the heart, liver, skeletal muscle, kidneys, and brain

Hepatic metabolism

Excreted via the kidneys. Large doses may be renally excreted.

Enrichment of flour and cereal products has decreased the risk of Thiamine deficiency in healthy patients

Question 6

What is the function of Vitamin B2 (Riboflavin) in the body?

Answer 6

Vitamin B2 acts as a coenzyme in ATP production through the metabolism of carbohydrates, fats, and proteins.

Question 7

What are the indications for Vitamin B2 supplementation?

Answer 7

Vitamin B2 is used for treatment of deficiency (typically with other B Vitamins) and as an adjunct in migraine prevention.

Reduce symptoms of fatigue
Help patient with cataracts due to antioxidants scavenger free radical effects
Helps in headache

Question 8

How is Vitamin B2 absorbed and excreted?

Answer 8

Vitamin B2 is absorbed in the upper ileum and is widely distributed in tissues, with minimal storage.

It is excreted in the urine unchanged.

Question 9

What are the side effects of Vitamin B2 supplementation?

Answer 9

No significant drug interactions or side effects

Vitamin B2 may cause yellow discoloration of sweat and urine and breastfeeding milk

Question 10

What is the role of Vitamin B3 (Niacin)?

Answer 10

Vitamin B3 is converted to NAD (Nicotinic Adenine Dinucleotide) and NADP (Nicotinic Adenine Dinucleotide Phosphate), which serve as coenzymes for lipid and protein metabolism.

Question 11

What are the indications for Vitamin B3 (Niacin) supplementation?

Answer 11

Vitamin B3 is indicated for hypercholesterolemia and reducing cholesterol levels in the blood.

Liver makes fatty acids to produce Triglycerides which are used in VLDL (Very Low Density Lipoproteins) synthesis.
Niacin (B3) lowers VLDL and increases HDL (High Density Lipoprotein)

Can be taken OTC as substitute for Cholesterol-lowering drugs (Statins)

Question 12

What are common side effects of high-dose (B3) Niacin?

Answer 12

Side effects include:

Flushing (caused by vasodilation of cutaneous vessels, typically with pruritis and tingling. Felt to be related to Prostaglandin release and is offset by pretreatment with Aspirin or use of sustained release [ER] formulation of Niacin [B3])

Hepatic dysfunction
GI (abdominal discomfort, and nausea)
Reduced glucose tolerance (typically reversible, MOA unclear)

Question 13

How does Niacin (B3) affect lipid levels in the body?

Answer 13

Niacin decreases VLDL and increases HDL, which can lower cholesterol levels in the blood.

In large amounts (500-1,500 mg daily)

Question 14

Where does Vitamin B3 (Niacin) come from?

Answer 14

Can be from diet
But foods are not fortified with enough to provide lipid lowering effects

Question 15

What is the role of Vitamin B6 (Pyridoxine) in the body?

Answer 15

Vitamin B6 is essential for the production of Vitamin B12 and folate, metabolism of amino acids, and can be used as an antidote for certain drug toxicities (like Ethanol, Mushrooms, and Isoniazid - a drug used to treat TB)

Question 16

What are the indications for Vitamin B6 supplementation?

Answer 16

Vitamin B6 is used for morning sickness, nausea, and sideroblastic anemias (secondary to Isoniazid and Pyrazinamide), and as an antidote for toxicity from isoniazid, mushrooms, and ethanol.

Question 17

What is the role of Vitamin B12 and Folic Acid in the body?

Answer 17

Both Vitamin B12 and Folic Acid are crucial for DNA synthesis and cell maturation.

Question 18

What are the indications for Vitamin B12 supplementation?

Answer 18

Vitamin B12 is used to treat pernicious anemia, megaloblastic anemia, and macrocytic anemia caused by poor B12 absorption.

Question 19

What are the indications for Folic Acid supplementation?

Answer 19

Folic Acid is used for megaloblastic anemia and macrocytic anemia, neural tube defect prevention, and as an adjunct in methotrexate toxicity (any med that cause decrease in folic acid like Depakote, patient is recommended to take folic acid) and pernicious anemia (with Vitamin B12).

Question 20

What are the effects of Vitamin B12 deficiency?

Answer 20

Vitamin B12 deficiency can cause abnormal DNA replication, leading to large dysfunctional RBC precursors
And potential nervous system issues (inflammation, demyelination, and neuronal cell deaths)

New onset of numbness, tingling
Check B12 level in addition to blood tests

Question 21

Vitamin B12 absorption? Treatment? Vegetarians?

Answer 21

Gastric Intrinsic Factor facilitates absorption of B12
Absorption is pH sensitive

Intrinsic Factor secreted by Parietal Cells, patients with gastric surgery may be deficient
Can’t absorb B12, need lifelong supplementation

Treatment for patients with disruption of parietal cells with IM B12 which bypasses the Intrinsic Factor

Vegetarians at higher risk for vitamin B12 deficiency

Question 22

Folic Acid metabolism? Deficiency? Women of childbearing age?

Answer 22

Folic Acid critical in Methionine and Homocysteine metabolism

Deficiency results in high incidence of neural tube defects and impaired resulting in anemias

Women of childbearing age should take Folic Acid supplementation

Question 23

What is the mechanism of iron in the body?

Answer 23

Iron is primarily stored in hemoglobin and myoglobin, recycled from old RBCs, and delivered to the liver and bone marrow by transferrin for RBC production.

Iron stored in the form of Hemoglobin, Myoglobin, Ferritin, and less degree of Transferrin

Question 24

What are the indications for iron supplementation?

Answer 24

Iron is indicated for the prevention and treatment of iron deficiency anemia.

IV Iron for patients who can’t tolerate Oral iron treatment and prevention

But Anaphylaxis-like reaction has been seen in IV formulation

Question 25

What is Iron Deficiency Anemia caused by?

Answer 25

1- Malnutrition

2- Any chronic blood loss:
Menstruation (fibrosis)
GI Bleed
Cancers

3- Increase Utilization:
Pregnancy
Recombinant Erythropoietin administration (common in renal failure)

Question 26

What does Iron Deficiency Anemia result in?

Answer 26

Small pale RBC, microcytic hypochromic anemia

RBC size is measured by Mean Cell Volume (MCV)

Goal of therapy is to correct anemia and replace deficient body stores

Can take 6-12 months of oral iron therapy

Symptoms:
Worsened restless legs in some patients
If new onset, continuous need to move legs around at rest
Do iron profile, look at Total Iron Binding Capacity, Total Iron Level, Ferritin % saturation

Question 27

What are common oral and IV iron supplements?

Answer 27

1- Oral iron supplements include:
Ferrous sulfate (most common tablet, 20% so 325mg has 65mg ferrous sulfate, from animal so best absorbed)
Ferrous fumarate, ferrous gluconate, and polysaccharide-iron complex.

IV iron supplements include:
Iron dextran, sodium ferric gluconate, and iron sucrose.
For severe responses, can’t take iron, or severe deficiency

Question 28

What factors can affect iron absorption?

Answer 28

Iron absorption can be affected by antacids, H2 blockers (OTC Famotidine [pepsid]), proton pump inhibitors (Omeprazole [Prilosec], or Lensoprazole [Previcid]), calcium supplements (or milk)

Enhanced by ascorbic acid (Vitamin C).

Animal iron (ferrous, heme iron) is better absorbed than vegetarian iron (ferric, non heme iron)

Question 29

What are the side effects of iron supplementation?

Answer 29

Side effects include gastrointestinal symptoms (common and dose related) like nausea, epigastric discomfort, constipation (mostly), diarrhea (sometimes), and black stools (can complicate ability to diagnose GI Bleeding).

Question 30

What is a major risk of iron toxicity?

Answer 30

Iron toxicity can occur in conditions such as hemochromatosis, hemosiderosis (both iron storage diseases), and iron-loading anemias like thalassemia.