Anemia Drugs Flashcards
Hematopoiesis
formation of new blood cells (myeloid tissue or bone marrow) - erythrocytes, leukocytes, thrombocytes
Anemias concern which cell?
erythrocytes
erythropoietin
Erythrocytes formation is driven by erythropoietin (hormone produced by the kidneys)
Reticulocytes
immature erythrocytes = take 24-36H to mature
Lifespan of erythrocytes
120 days
Four types of anemia
RBC Maturation Defect:
- Cytoplasmic
- Nuclear
Excessive RBC Destruction (Hemolytic):
- Intrinsic RBC Abnormalities
- Extrinsic Mechanisms
Cytoplasmic Anemia
◦ Fe deficiency (blood loss, surgery, childbirth, GIB, menstrual blood loss)
◦ Thalassemia (genetic disorder – defective globulin synthesis)
◦ Cell are :
◦ microcytic (small) decreased MCV
◦ hypochromic (pale) decreased MCHC
Nuclear Anemia
◦ Defects in DNA or protein synthesis
◦ Deficit in Vitamin B12 and/or Folate (Vitamin B9) (both required for DNA and protein synthesis)
◦ Pernicious Anemia (lack of intrinsic factor in
stomach which inhibits absorption of Vitamin B12)
◦ Megaloblastic Anemia (due to deficient intake of
Vitamin B12 and/or Folate)
◦ Cells are:
◦ Macrocytic (large) increased MCV
◦ Normochromic (normal colour) normal MCHC
Intrinsic RBC Abnormalities (Anemia)
◦ Genetic defect
◦ Sickle cell anemia, hereditary spherocytosis
◦ Erythrocytes appear as spherocytes
Extrinsic Mechanisms (Anemia)
◦ Drugs induce antibodies that target and destroy RBCs
◦ Septic shock resulting in disseminated intravascular coagulation (DIC)
◦ Mechanical forces of certain medical devices
◦ Erythrocytes appear as spherocytes
Anemia of Chronic Disease
◦ Caused by chronic inflammation, autoimmune, infectious or malignant diseases
◦ Primarily immune driven – cytokines cause retention of Fe by macrophages
◦ Underproduction of erythrocytes and mild shortening of lifespan
◦ Erythrocytes are normocytic, normochromic and hypoproliferative
◦ Typically a mild anemia, occasionally severe requiring blood transfusion
◦ Treatment aimed at treating underlying cause
◦ Characterized by increased ferritin, normal folate, and cobalamin
Anemia Drugs to know
◦Iron
◦Folate (Vitamin B9)
◦Cyanocobalamin(Vitamin B12)
◦Epoetin Alfa
Is iron an essential mineral in the body
yes
What is iron used for in the body mainly?
Oxygen carrier in hemoglobin and myoglobin
Where is iron stored?
liver, spleen, and bone marrow
Deficiency in iron results in what?
anemia
Dietary sources of iron
meats, certain vegetables and grains
Which foods enhance iron absorption?
Orange juice, Veal, Fish, Ascorbic acid
In which form are oral iron preparations available in?
Feeous salts, such as ferrous fumarate (Femiron), ferrous gluconate, ferrous sulphate (FeSO4)
Parental iron preparations
◦ iron dextran (Dexiron, Infufer)
◦ iron sucrose (Venofer)
◦ ferric gluconate (Ferrlecit)
◦ ferumoxytol (Feraheme)
Iron Classification
Iron
Iron Movement
varies depending on particular formulation
Iron Action
absorbed in small amount in small intestine; transformed into ferrous form, bound to transporter and moves into bloodstream; Fe is used in bone marrow to make Hgb; excess is stored as ferritin in
Iron Nursing Considerations
Most common cause of pediatric poisoning deaths; Contraindications: allergy; hemochromatosis (Fe
overload), hemolytic anemia or other anemia not associated with Fe deficiency; Adverse effects: nausea,
vomiting, diarrhea, constipation, and stomach cramps and pain; black, tarry stools (also a sign of GIB –
educate); Liquid oral preparations temporarily discolor teeth; Injectable forms cause pain upon injection
Iron Indication
Prevention and treatment of iron deficiency syndromes; Administration of iron alleviates the symptoms of
iron deficiency anemia, but the underlying cause of the anemia should be corrected.
Iron administration
PO or IV, doses vary; Some foods enhance iron absorption: Orange juice, Veal, Fish, Ascorbic acid
Iron Nursing Implications and assessments
◦ Assess patient history and medication history, including drug allergies.
◦ Assess potential contraindications.
◦ Assess baseline laboratory values, especially hemoglobin, hematocrit, reticulocytes, and others.
◦ Obtain nutritional assessment.
◦ For liquid iron preparations, follow the manufacturer’s guidelines on dilution and administration.
◦ Instruct the patient to take liquid iron preparations through a straw to avoid staining tooth enamel.
◦ Oral forms of iron should be taken between meals for maximum absorption but may be taken with
meals if gastrointestinal distress occurs.
◦ Oral forms should be given with juice but not with milk or antacids.
◦ To avoid esophageal corrosion, patients should remain upright for up to 30 minutes after taking oral
iron doses.
◦ Patients should be encouraged to eat foods high in iron and folic acid.
Folic Acid (Vitamin B9) Classification
Water-soluble, B-complex vitamin; Essential for erythropoiesis; aka Folate
Folic Acid (Vitamin B9) Movement
onset unknown, peak 60-90min, ½ life unknown, duration unknown
Folic Acid (Vitamin B9) Action
Essential for erythropoiesis and synthesis of RNA and DNA
Folic Acid (Vitamin B9) Nursing Considerations
Should not be used until actual cause of anemia is determined; May mask symptoms of pernicious anemia, which requires treatment other than folic acid; Untreated pernicious anemia progresses to neurological damage Contraindications – allergy, anemias other than folic acid deficiency; adverse reactions - rare
Folic Acid (Vitamin B9) Indications
Folic acid deficiency; Malabsorption syndromes are the most common causes of deficiency; given during pregnancy, to prevent neural tube defects
Folic Acid (Vitamin B9) Administration
Administer oral folic acid with food; Folic acid is available for both oral and injectable use
Cyanocobalamin(Vitamin B12) Classification
water soluble B complex vitamin that contain cobalt
Cyanocobalamin(Vitamin B12) Movement
onset unknown, peak 8-12H, ½ life 6 D, duration unknown
Cyanocobalamin(Vitamin B12) Action
required coenzyme for many metabolic pathways – fate and CHO metabolism and protein
synthesis
Cyanocobalamin(Vitamin B12) Nursing consideration
Contraindications: allergy
adverse effects: only at large doses – itching, diarrhea, fever
Cyanocobalamin(Vitamin B12) Indication
Used to treat pernicious anemia and other megaloblastic anemias
Cyanocobalamin(Vitamin B12) Administration
Administered orally or parentally; given IM until normal serum levels achieved, then oral route now preferred – given daily once Vitamin B12 levels are normal; maintenance doses: 50-100mcg PO daily, 100 mcg/month IM
Epoetin Alpha Classification
epoetin alpha (Eprex); Longer-acting form of epoetin is called darbepoetin (Aranesp)
Epoetin Alpha Movement
onset 7-10d peak 5-24H, ½ life 4-13H, duration variable (Eprex
Epoetin Alpha Action
biosynthetic erythropoietin - stimulates synthesis of erythrocytes
Epoetin Alpha Nursing Considerations
Medication is ineffective without adequate body iron stores and bone marrow function; Most patients
receiving epoetin alfa need to also receive an oral iron preparation;
Contraindications: drug allergy;
uncontrolled hypertension; hemoglobin levels that are above 100 mmol/L for cancer patients and 130 mmol/L
for patients with kidney disease; head and neck cancers; risk of thrombosis;
Adverse Effects: hypertension, fever, headache, pruritus, rash, nausea, vomiting, arthralgia, and injection site reaction
Epoetin Alpha Indication
treatment of anemia associated with end-stage renal disease, chemotherapy-induced anemia, and anemia
associated with zidovudine therapy
Epoetin Alpha Administration
SC or IV; performance enhancing drug - ‘doping’
