Module 4: Oral Iron Supplements

Question 1

What is the indication for oral iron supplements?

Answer 1

Iron deficiency anemia.

Iron deficiency without anemia.

Nutritional support to prevent deficiency.

Question 2

What is the therapeutic goal with use of oral iron supplements?

Answer 2

Replace iron stores and encourage erythropoiesis and oxygen transportation.

Question 3

What is the MOA of oral iron supplements?

Answer 3

1. The body absorbs iron from small intestine.
2. Stored in macrophages as ferritin.
3. Ferritin converted to an absorbable form of iron.
4. Transferrin carries the iron to bone marrow cells, which then produce RBCs
5. The RBCs transport oxygen throughout the body.

Question 4

What are the pharmacokinetic considerations of iron supplements?

Answer 4

E.g. Ferrous sulfate

A: Iron absorbed in duodenum and upper jejunum; in persons with normal iron stores, 10% of oral dose is absorbed; increased to 20-30% in adequate stores. Food and achlorhydria will decrease absorption.

D: Protein binding to transferrrin.

M: N/A

E: Urine, seat, sloughing of intestinal mucosa, and menses

Onset: 3-10 days

Peak: reticulocytosis = 5-10 dyas; hemoglobin increases within 2-4 weeks

Question 5

What are some special prescribing considerations?

Answer 5

Older adult = lower doses may be as effective with less GI adverse effects

Avoid in patients with peptic ulcer, enteritis, or ulcerative colitis

Avoid in patients receiving frequent blood transfusions

Pediatric = accidental overdose is a leading cause of fatal poisoning in children under 6

Question 6

What are pregnancy and lactation considerations?

Answer 6

Used in pregnancy as iron deficiency can be associated with adverse pregnancy outcomes.

Lactation - safe

Question 7

What are common side effects of oral iron supplements?

Answer 7

GI; constipation, dark stools, epigastric pain, nausea.

Question 8

What are significant drug interactions with ferrous sulfate?

Answer 8

No signifiant reactions. Some mediations may increase or decrease absorption.

Question 9

What are contraindications and cautions with ferrous sulfate?

Answer 9

Contraindicated:
- anemia not d/t iron deficiency
- hemochromatosis
- hemosiderosis
- hypersensitivity to iron products

Caution:
- PUD
- Ulcerative colitis or regional enteritis
- alcoholism
- severe hepatic impairment
- severe renal impairment

Question 10

What are monitoring parameters for ferrous sulfate?

Answer 10

Hgb and HCT, consider RBC count, RBC indices, serum ferritin, transferrin saturation, total iron-binding capacity, serum iron concentration, erythrocyte protoporphyrin concentration