Introduction to Clinical Pharmacology Chapter 51 Immunomodulating Drugs

CSFs are a group of immunostimulants used in cancer treatment and chronic renal failure to support the hematopoietic system. other agents used to modify the immune system—immunosuppressants—is also included.

Types and Functions of Blood Cells Red blood cells (erythrocytes): supply oxygen White blood cells (leukocytes): protect against microorganisms Platelets (megakaryocytes): control bleeding

Drugs Used in Treatment of Anemia and Bleeding and Prevention of Infection Colony-stimulating factors Oprelvekin Erythropoiesis-stimulating agents Iron preparations Folic acid Vitamin B12

Drugs Used to Stimulate White Blood Cells: Actions and Uses Colony-stimulating factors (CSF): glycoproteins act on hematopoietic cells to stimulate proliferation, differentiation, and maturation of white blood cells, used to treat or prevent infection (by minimizing neutropenia) Filgrastim: used after a cycle of chemotherapy;The absolute neutrophil count (ANC) is monitored and therapy is continued until 10,000/mm3 is achieved. Pegfilgrastim: used as single dose between chemotherapy cycle Sargramostim: used following BMT and induction chemotherapy used with leukemia, and to stimulate stem cells for harvest

Drugs Used to Stimulate White Blood Cells: Adverse Reactions Bone pain Hypertension Nausea and vomiting Alopecia Hypersensitivity or allergic reactions

Drugs Used to Stimulate White Blood Cells: Contraindications, Precautions, and Interactions Contraindicated in patients with hypersensitivity Pregnancy category C, caution when breastfeeding Filgrastim: caution with hypothyroid disease Pegfilgrastim: causes sickle cell crisis Can stimulate cancer cell growth Increased neutrophils when used with lithium

Drugs Used to Stimulate Blood Platelets: Actions and Uses Oprelvekin: acts to stimulate thrombopoiesis Reduces need for multiple platelet transfusions Used to treat or prevent thrombocytopenia associated with chemotherapy for solid tumor cancer treatments eltrombopag and romiplostim are used only for ITP and are not to be used to increase platelet count associated with immunosuppression during chemotherapy.

Drugs Used to Stimulate Blood Platelets: Adverse Reactions General reactions: Fluid retention, peripheral edema, dyspnea, syncope, fever, allergic reaction Cardiovascular reactions: Tachycardia, palpitations, atrial fibrillation, arrhythmias resulting in stroke and pulmonary edema, capillary leak syndrome

Drugs Used to Stimulate Blood Platelets: Contraindications, Precautions, and Interactions Contraindicated in patients with hypersensitivity and not used with chemotherapy that is extremely myelosuppressive Use cautiously in patients with renal and heart failure or atrial arrhythmias Low potassium (hypokalemia) can occur with cancer chemotherapy agent ifosfamide Pregnancy category C; stop breastfeeding Anaphylactic-type reactions: discontinue use

Drugs Used in Treating Anemia Associated With Chronic Illness: Actions and Uses Epoetin alfa: drug that stimulates erythropoiesis Used to treat anemia associated with chronic renal failure; chemotherapy for cancer treatment; zidovudine therapy for human immunodeficiency virus; postsurgical blood replacement in place of allogeneic transfusions Darbepoetin alfa, an erythropoiesis-stimulating protein: used to treat anemia

Drugs Used in Treating Anemia Associated With Chronic Illness: Adverse Reactions Hypertension; headache; nausea; vomiting; diarrhea; rashes; fatigue; arthralgia; skin reaction at injection site

Drugs Used in Treating Anemia Associated With Chronic Illness: Contraindications and Precautions Epoetin alfa: contraindicated in patients with uncontrolled hypertension; those needing emergency transfusion; those with hypersensitivity to human albumin Darbepoetin alfa: contraindicated in patients with uncontrolled hypertension, those allergic to drug Epoetin alfa darbepoetin alfa: used with caution in patients with hypertension; heart disease; congestive heart failure; history of seizures

Drugs Used in Treating Iron Deficiency Anemia: Actions and Uses Iron preparations: Act by elevating serum iron concentration, which replenishes hemoglobin and depleted iron stores Iron is best absorbed on an empty stomach. Parenteral iron: Used when patient cannot take oral drugs or when patient experiences gastrointestinal intolerance to oral iron administration; treating iron deficiency anemia

Drugs Used in Treating Iron Deficiency Anemia: Adverse Reactions and Contraindications Adverse reactions: gastrointestinal reactions: GI irritation, vomiting, constipation, diarrhea, darker stools; generalized system reactions, headache, backache, allergic reactions Iron supplements: contraindicated in patients with known hypersensitivity to drug or any component of the drug

Drugs Used in Treating Iron Deficiency Anemia: Contraindications and Precautions Iron compounds Contraindicated in patients with hemochromatosis or hemolytic anemia Used cautiously in patients with hypersensitivity to aspirin

Drugs Used in Treating Iron Deficiency Anemia: Interactions Interactant drug Effect of interaction Antibiotics Decreased GI absorption of the antibiotic Levothyroxine Decreased absorption of levothyroxine Levodopa, methyldopa Decreased effect of anti- Parkinson’s medication Ascorbic acid (vitamin C) Increased absorption of iron

Drugs Used in Treating Folic Acid Deficiency Anemia: Action and Uses Folic acid: used in treating megaloblastic anemia; for women of childbearing age to decrease incidence of neural tube defects Leucovorin: used to diminish hematologic effects of methotrexate Used in treating certain types of cancer

Drugs Used in Treating Folic Acid Deficiency Anemia: Contraindications, Precautions, and Interactions Folic acid, leucovorin: contraindicated for treating pernicious anemia, other anemias in which vitamin B12 is deficient Used cautiously within RDA guidelines Pregnant women with folate deficiency are at increased risk for complications of pregnancy, fetal abnormalities Signs of folate deficiency: occur when sulfasalazine administered concurrently Increase in seizure activity: occurs when folic acid is administered with hydantoins

Drugs Used in Treating Vitamin B12 Deficiency Anemia: Actions, Uses, and Adverse Reactions Vitamin B12 used to treat patients with a vitamin B12 deficiency; also used to perform the Schilling test Adverse reactions: mild diarrhea; itching; increase in RBC production; acne; peripheral vascular thrombosis; congestive heart failure; pulmonary edema

Drugs Used in Treating Vitamin B12 Deficiency Anemia: Contraindications, Precautions, and Interactions Contraindicated in patients allergic to cyanocobalamin Administered cautiously during pregnancy, in patients with pulmonary disease, anemia Alcohol, neomycin, colchicine decrease the absorption of oral vitamin B12

Nursing Process: Assessment #1 Preadministration assessment: Obtain general health history, ask about symptoms of anemia Take vital signs to provide baseline during therapy Physical assessments: patient’s general appearance and, in severely anemic patient, evaluation of patient’s ability to carry out activities of daily living

Nursing Process: Assessment #2 Ongoing assessment: Monitor patient for adverse reactions; report any occurrence of adverse reactions to primary health care provider before next dose is due Inform patient that color of stool will become darker or black Assess patient for relief of symptoms of anemia

Nursing Diagnoses Fatigue related to dilutional anemia caused by fluid retention Imbalanced Nutrition: Less Than Body Requirements related to lack of iron, folic acid, other (specify) in the diet Constipation related to adverse reaction to iron therapy

Nursing Process: Planning The expected outcomes include: Optimal response to therapy Supporting the patient needs related to the management of adverse reactions Understanding of and compliance with prescribed treatment regimen

Nursing Process: Implementation #1 Promoting an optimal response to therapy: Iron: check with hospital pharmacist regarding simultaneous administration of iron salts with other drugs; monitor patient for allergic response for at least 1 hour after test dose and before administering remaining dose Vitamin B12: patients with vitamin B12 anemia are treated with vitamin administered by parenteral route weekly

Nursing Process: Implementation #2 Promoting an optimal response to therapy (cont.) Epoetin alfa: monitor blood pressure closely; report any rise of 20 mm Hg or more in systolic, diastolic pressure to primary health care provider

Nursing Process: Implementation #3 Monitoring and managing patient needs: Altered nutrition: recommend balanced diet with emphasis on foods that are high in iron, folic acid, or vitamin B12; monitor amount of food eaten at meals; vegetarian patient: dietitian should be consulted to provide menus with appropriate iron-rich foods Constipation: instruct patient to increase fluid intake to 10 to 12 glasses of water daily, eat a diet high in fiber, and increase activity

Nursing Process: Implementation #4 Educating the patient and family: Explain medical regimen thoroughly to patient and family Emphasize importance of following the prescribed treatment regimen Iron: Take this drug with water on empty stomach; if gastrointestinal upset occurs, take drug with food or meals

Nursing Process: Implementation #5 Educating the patient and family (cont.) Iron (cont.) This drug causes darkening of stools, constipation, or diarrhea; if constipation or diarrhea becomes severe, contact primary health care provider Iron deficiency occurs: cause must be determined and therapy should be under the care of a health care provider

Nursing Process: Implementation #6 Educating the patient and family (cont.) Epoetin alfa: Strict compliance with antihypertensive drug regimen: important in patients with known hypertension during epoetin alfa therapy Adverse reactions: dizziness; headache; fatigue; joint pain; nausea; vomiting; diarrhea

Nursing Process: Implementation #7 Educating the patient and family (cont.) Folic acid: Avoid use of multivitamin preparations unless such use has been approved by the primary health care provider Follow diet recommended by primary health care provider because diet and drug are necessary to correct a folic acid deficiency

Nursing Process: Implementation #8 Educating the patient and family (cont.) Leucovorin: Megaloblastic anemia: adhere to diet prescribed by the primary health care provider If purchase of foods high in protein becomes a problem, discuss this with primary health care provider

Nursing Process: Implementation #7 Educating the patient and family (cont.) Vitamin B12: Nutritional deficiency of vitamin B12: eat a balanced diet that includes seafood, eggs, meats, and dairy products Pernicious anemia: lifetime therapy is necessary, avoid contact with infections, report any signs of infection to primary health care provider immediately

Nursing Process: Evaluation Therapeutic effect of the drug is achieved Patient has normal bowel movements An adequate nutritional intake is achieved Patient and family demonstrate an understanding of the drug regimen Patient verbalizes the importance of complying with the prescribed treatment regimen

Question #1 Is the following statement true or false? The hematopoietic system is composed of fluid and four types of cells.

Answer to Question #1 False The hematopoietic system is composed of fluid and three types of cells. RBCs supply the body with oxygen, white blood cells protect the body from microorganisms, and platelets control bleeding.

Question #2 Is the following statement true or false? Chronic diseases like kidney failure or treatments such as chemotherapy can reduce cells in the circulation, causing fatigue, bleeding, or infection.

Answer to Question #2 True Chronic diseases like kidney failure or treatments such as chemotherapy can reduce cells in the circulation, causing fatigue, bleeding, or infection. Colony-stimulating factors are one type of immunostimulant that can boost the number of cells.

Question #3 Is the following statement true or false? Anemia is a condition caused by increased amounts of hemoglobin, causing more oxygen to be delivered to the tissues.

Answer to Question #3 False Anemia is a condition caused by reduced amounts of hemoglobin, causing less oxygen to be delivered to the tissues. Anemia occurs due to chronic illnesses or specific deficiencies such as iron.