Medications Used in Prenatal/ Antepartum – Flashcards

Drug Category: vitamins Therapeutic Effects: Treatment and prevention of vitamin deficiencies. Special formulations are available for patients with particular needs, including: Prenatal multiple vitamins (with larger doses of folic acid), PK and PD: Well absorbed from the GI tract after oral administration; some processes are active, some are passive. Absorption of water-soluble vitamins generally increases in deficiency states. Absorption of some lipid-soluble vitamins may require bile acids. Distribution: Widely distributed; cross the placenta and enter breast milk. Fat-soluble vitamins (A, D, E, and K) are stored in fatty tissues and the liver. Contraindications: Hypersensitivity to preservatives, colorants, or additives, including tartrazine, saccharin, and aspartame (oral forms) Primary Adverse Effects: nausea/vomitting In recommended doses, adverse reactions are extremely rare GU: urine discoloration (preparations with B vitamins) Misc: allergic reactions to preservatives, additives, or colorants Dosage/Route/Frequency: 1One a day, orally; Started as soon as pg is confirmed DDI: Large amounts of vitamin B may interfere with the beneficial effect of levodopa . Nursing Assessments: Take midday after a meal Need to emphasize that it does not replace a healthy prenatal diet Nursing Diagnoses: Expected Outcomes/ measurements of outcome and documentation: Teaching: Encourage patient to comply with recommendations of health care professional. Explain that the best source of vitamins is a well-balanced diet with foods from the 4 basic food groups.

Iron supplement - one tab, once or twice daily Not other forms of iron (ferrin, ferrite, ferric); sulfate is best absorbed Include iron-rich foods in teaching (later in course) Drug Category: iron supplements Therapeutic Effects: Treatment & prevention iron deficiency anemia PK and PD: Approximately 5-10% of dietary iron is absorbed (up to 30% in deficiency states). Therapeutically administered PO iron is up to 60% absorbed via active and passive transport processes. Contraindications: Anemia not due to iron deficiency Hemochromatosis Hemosiderosis Hypersensitivity to iron products. Primary Adverse Effects: Dangerous if other children in house: look like M&M candy Very common poisoning of young children nausea/vomiting/constipation/dark stools, epigastric pain, GI bleeding, vomiting dizziness, headache, syncope Dosage/Route/Frequency: one tab, once or twice daily PO: (Adults) Deficiency -2-3 mg/kg/day in 2-4 divided doses or 60-100 mg elemental iron twice daily. Prophylaxis- 60-100 mg elemental iron daily. DDI: Iron absorption is ↓ 33-50% by concurrent administration of food. Doses of ascorbic acid ≥200 mg may ↑ absorption of iron by up to 30% ↓ absorption of tetracyclines, fluoroquinolonesbisphosphonates, levothyroxine, mycofenolate mofetil, and penicillamine (simultaneous administration should be avoided). ↓ absorption of and may ↓ effects of levodopa and methyldopa . Concurrent administration of proton pump inhibitors, histamine H2 antagonists, and cholestyramine may ↓ absorption of iron. Chloramphenicol and vitamin E may ↓ hematologic response to iron therapy. Nursing Assessments: Take midday with food - Vitamin C enhances absorption If constipated, increase water and fiber in diet. Notify physician or other health care professional and use appropriate nursing measures should these occur. Lab Test Considerations: Monitor hemoglobin, hematocrit, and reticulocyte values prior to and every 3 wk during the first 2 mo of therapy and periodically thereafter. Serum ferritin and iron levels may also be monitored to assess effectiveness of therapy. Avoid using antacids, coffee, tea, dairy products, eggs, or whole-grain breads with or within 1 hr after administration of ferrous salts. Iron absorption is decreased by 33% if iron and calcium are given with meals. Nursing Diagnoses: Expected Outcomes/ measurements of outcome and documentation: Increase in hemoglobin, which may reach normal parameters after 1-2 mo of therapy. Improvement of iron deficiency anemia. Teaching: Include iron-rich foods in teaching. Take midday with food - Vitamin C enhances absorption Do not take with dairy products: poor absorption If constipated, increase water and fiber in diet. Dangerous if other children in house: look like M&M candy

Drug Category: water soluble vitamins Therapeutic Effects: Fetal development: helps the neural tube to grow and close assists cell production and division -- including RBCs PK and PD: Well absorbed from the GI tract and IM and subcut sites. Crosses the placenta. Contraindications: Uncorrected pernicious, aplastic, or normocytic anemias (neurologic damage will progress despite correction of hematologic abnormalities); Primary Adverse Effects: irritability, difficulty sleeping, malaise, confusion, fever, rash Dosage/Route/Frequency: Females of child-bearing potential -0.4-0.8 mg/day. DDI: Pyrimethamine, methotrexate, trimethoprim, and triamterene prevent the activation of folic acid (leucovorin should be used instead to treat overdoses of these drugs). Absorption of folic acid is ↓ by sulfonamides (including sulfasalazine ), antacids, and cholestyramine . Folic acid requirements are ↑ by estrogens, phenytoin, phenobarbital, primidone, carbamazepine, or corticosteroids . May ↓ phenytoin levels. Nursing Assessments: Assess patient for signs of megaloblastic anemia (fatigue, weakness, dyspnea) before and periodically throughout therapy. Lab Test Considerations: Monitor plasma folic acid levels, hemoglobin, hematocrit, and reticulocyte count before and periodically during therapy. May cause ↓ serum concentrations of other B complex vitamins when given in high continuous doses. Antacids should be given at least 2 hr after folic acid; Nursing Diagnoses: Expected Outcomes/ measurements of outcome and documentation: Prevention of neural tube defects. Teaching: Folic acid in early pregnancy is necessary to prevent neural tube defects. Foods high in folic acid include vegetables, fruits, and organ meats; heat destroys folic acid in foods. Explain that folic acid may make urine more intensely yellow. Instruct patient to notify health care professional if rash occurs, which may indicate hypersensitivity.

Drug Category: adrenergics Therapeutic Effects: Relatively selective for beta2(pulmonary)-adrenergic receptor sites, with less effect on beta1(cardiac)-adrenergic receptors. Reversal drug for pitocin Management of preterm labor (tocolytic) (the FDA has recommended that injectable terbutaline should not be used in pregnancy for the prevention or prolonged treatment [>48-72 hr] of preterm labor in either the inpatient or outpatient settings because of the potential for serious maternal heart problems and death; oral terbutaline should not be used for the prevention or any treatment of preterm labor because of a lack of efficacy and the potential for serious material heart problems and death). PK and PD: 35-50% absorbed following oral administration but rapidly undergoes first-pass metabolism. Well absorbed following subcut administration. Contraindications: Hypersensitivity to adrenergic amines Use Cautiously in: Cardiac disease; Hypertension; Hyperthyroidism; Diabetes; Glaucoma; Primary Adverse Effects: Cardiovascular adverse effects (typically Beta1 effects) CNS stimulant effects Risk of pulmonary edema is big risk (check breath sounds) CNS: nervousness, restlessness, tremor, headache, insomnia Resp: pulmonary edema CV: angina, arrhythmias, hypertension, myocardial ischemia, tachycardia GI: nausea, vomiting Endo: hyperglycemia F and E: hypokalemia Cardiovascular adverse effects (typically Beta1 effects) CNS stimulant effects Risk of pulmonary edema is big risk Dosage/Route/Frequency: IV: (Adults) Tocolysis- 2.5-10 mcg/min infusion; ↑ by 5 mcg/min q 10 min until contractions stop (not to exceed 30 mcg/min). After contractions have stopped for 30 min, ↓ infusion rate to lowest effective amount and maintain for 4-8 hr (unlabeled). DDI: Concurrent use with other adrenergics (sympathomimetic) will have additive adrenergic side effects. Use with MAO inhibitors may lead to hypertensive crisis. Beta blockers may negate therapeutic effect. Nursing Assessments: Monitor maternal pulse and BP, frequency and duration of contractions, and fetal heart rate. Notify health care professional if contractions persist or increase in frequency or duration or if symptoms of maternal or fetal distress occur. Maternal side effects include tachycardia, palpitations, tremor, anxiety, and headache. Assess maternal respiratory status for symptoms of pulmonary edema (increased rate, dyspnea, rales/crackles, frothy sputum). Monitor mother and neonate for symptoms of hypoglycemia (anxiety; chills; cold sweats; confusion; cool, pale skin; difficulty in concentration; drowsiness; excessive hunger; headache; irritability; nausea; nervousness; rapid pulse; shakiness; unusual tiredness; or weakness) and mother for hypokalemia (weakness, fatigue, U wave on ECG, arrhythmias). Monitor maternal serum glucose and electrolytes. May cause hypokalemia and hypoglycemia. Monitor neonate's serum glucose, because hypoglycemia may also occur in neonates. Toxicity Overdose: Symptoms of overdose include persistent agitation, chest pain or discomfort, decreased BP, dizziness, hyperglycemia, hypokalemia, seizures, tachyarrhythmias, persistent trembling, and vomiting. Treatment includes discontinuing beta-adrenergic agonists and symptomatic, supportive therapy. Cardioselective beta blockers are used cautiously, because they may induce bronchospasm. Nursing Diagnoses: Expected Outcomes/ measurements of outcome and documentation: Control of preterm labor in a fetus of 20-36 wk gestational age. Teaching: Notify health care professional immediately if labor resumes or if significant side effects occur

Drug Category: corticosteroids Therapeutic Effects: Short-term administration to high-risk mothers before delivery to prevent respiratory distress syndrome in the newborn PK and PD: Widely distributed; crosses the placenta and probably enters breast milk. Metabolized mostly by the liver. Contraindications: Active untreated infections (may be used in patients being treated for tuberculous meningitis) Traumatic brain injury (high doses may ↑ mortality) Lactation: Avoid chronic use Some products contain bisulfites and should be avoided in patients with known hypersensitivity. Safety not established in OB. Primary Adverse Effects CNS: depression, euphoria, headache, ↑ intracranial pressure (children only), personality changes, psychoses, restlessness EENT: cataracts, ↑ intraocular pressure CV: hypertension GI: PEPTIC ULCERATION, anorexia, nausea, vomiting Derm: acne, ↓ wound healing, ecchymoses, fragility, hirsutism, petechiae Endo: adrenal suppression, hyperglycemia F and E: fluid retention (long-term high doses), hypokalemia, hypokalemic alkalosis Hemat: THROMBOEMBOLISM, thrombophlebitis Metabolic: weight gain, weight loss MS: muscle wasting, osteoporosis, avascular necrosis of joints, muscle pain Misc: cushingoid appearance (moon face, buffalo hump), ↑ susceptibility to infection Dosage/Route/Frequency: Prevention of respiratory distress syndrome in newborn- 12 mg daily for 2-3 days before delivery (unlabeled). DDI: Additive hypokalemia with thiazide and loopdiuretics, or amphotericin B . Hypokalemia may ↑ risk of digitalis glycoside toxicity. May ↑ requirement for insulins or oral hypoglycemic agents . Phenytoin, phenobarbital, and rifampin stimulate metabolism; may ↓ effectiveness. ↑ risk of adverse GI effects with NSAIDs (including aspirin). Nursing Assessments: Monitor intake and output ratios and daily weights. Observe patient for peripheral edema, steady weight gain, rales/crackles, or dyspnea. Notify health care professional if these occur. Monitor serum electrolytes and glucose. May cause hyperglycemia, especially in persons with diabetes. May cause hypokalemia. Patients on prolonged courses of therapy should routinely have hematologic values, serum electrolytes, and serum glucose evaluated. May ↓ WBC counts. May ↓ serum potassium and calcium and ↑ serum sodium concentrations. Guaiac-test stools. Promptly report presence of guaiac-positive stools. Nursing Diagnoses: Expected Outcomes/ measurements of outcome and documentation: prevent respiratory distress syndrome in the newborn Teaching: Instruct patient to inform health care professional promptly if severe abdominal pain or tarry stools occur. Patient should also report unusual swelling, weight gain, tiredness, bone pain, bruising, nonhealing sores, visual disturbances, or behavior changes.

Drug Category: minerals electrolytes Therapeutic Effects: Prevention of seizures associated with severe eclampsia, pre-eclampsia. Treatment of hypertension. Unlabeled use: Preterm labor. PK and PD: well absorbed. Widely distributed. Crosses the placenta Contraindications: Hypermagnesemia; Hypocalcemia; Anuria; Heart block; Avoid using for more than 5-7 days for preterm labor (may ↑ risk of hypocalcemia and bone changes in newborn); avoid continuous use during active labor or within 2 hr of delivery due to potential for magnesium toxicity in newborn. Primary Adverse Effects: CNS: drowsiness Resp: ↓ respiratory rate CV: arrhythmias, bradycardia, hypotension GI: diarrhea MS: muscle weakness Derm: flushing, sweating Metabolic: hypothermia Dosage/Route/Frequency: Eclampsia/Pre-Eclampsia IV: IM: (Adults) 4-5 g by IV infusion, concurrently with up to 5 g IM in each buttock; then 4-5 g IM q 4 hr or 4 g by IV infusion followed by 1-2 g/hr continuous infusion (not to exceed 40 g/day or 20 g/48 hr in the presence of severe renal insufficiency). Seizures/Hypertension IM: IV: (Adults) 1 g q 6 hr for 4 doses as needed. DDI: May potentiate calcium channel blockers and neuromuscular blocking agents . Nursing Assessments: High Alert: Accidental overdosage of IV magnesium has resulted in serious patient harm and death. Have second practitioner independently double-check original order, dose calculations, and infusion pump settings. Do not confuse milligram (mg), gram (g), or millequivalent (mEq) dosages. Hypomagnesemia/Anticonvulsant: Monitor pulse, BP, respirations, and ECG frequently throughout administration of parenteral magnesium sulfate. Respirations should be at least 16/min before each dose. Monitor neurologic status before and throughout therapy. Institute seizure precautions. Patellar reflex (knee jerk) should be tested before each parenteral dose of magnesium sulfate. If response is absent, no additional doses should be administered until positive response is obtained. Monitor newborn for hypotension, hyporeflexia, and respiratory depression if mother has received magnesium sulfate. Monitor intake and output ratios. Urine output should be maintained at a level of at least 100 mL/4 hr. Nursing Diagnoses: Expected Outcomes/ measurements of outcome and documentation: Control of seizures associated with toxemias of pregnancy. Teaching: Explain purpose of medication to patient and family.

Drug Category: mineral and electrolyte replacements/supplements Therapeutic Effects: Emergency treatment of hyperkalemia and hypermagnesemia PK and PD: IV administration results in complete bioavailability. Readily enters extracellular fluid. Crosses the placenta Contraindications: Hypercalcemia Renal calculi Ventricular fibrillation. Primary Adverse Effects: CNS: headche, tingling CV: syncope, CARDIAC ARREST, arrhythmias, bradycardia GI: constipation, nausea, vomiting GU: calculi, hypercalciuria Local: phlebitis Dosage/Route/Frequency: calcium antagonist toxicity (dosed as calcium gluconate) IV: (Adults) 500-800 mg (maximum 3 g/dose). DDI:Hypercalcemia increases the risk of digoxin toxicity. Chronic use with antacids in renal insufficiency may lead to milk-alkali syndrome. Ingestion by mouth decreases the absorption of orally administered tetracyclines, fluoroquinolones, phenytoin, and iron salts . Excessive amounts may decrease the effects of calcium channel blockers . Decreases absorption of etidronate and risedronate (do not take within 2 hr of calcium supplements). May decrease the effectiveness of atenolol . Concurrent use with diuretics (thiazide) may result in hypercalcemia. May decrease the ability of sodium polystyrene sulfonate to decrease serum potassium. Nursing Assessments: Monitor BP, pulse, and ECG frequently throughout parenteral therapy. May cause vasodilation with resulting hypotension, bradycardia, arrhythmias, and cardiac arrest. Transient increases in BP may occur during IV administration, especially in geriatric patients or in patients with hypertension. Monitor serum calcium or ionized calcium, chloride, sodium, potassium, magnesium, albumin, and parathyroid hormone (PTH) concentrations before and periodically during therapy for treatment of hypocalcemia. High Alert: Errors with IV calcium gluconate and chloride have occurred secondary to confusion over which salt is ordered. Clarify incomplete orders. Confusion has occurred with milligram doses of calcium chloride and calcium gluconate, which are not equal. Chloride and gluconate forms are routinely available on most hospital crash carts; physician should specify form of calcium desired. Doses should be expressed in mEq. High Alert: Administer slowly. High concentrations may cause cardiac arrest Nursing Diagnoses: Expected Outcomes/ measurements of outcome and documentation: Decrease in the signs and symptoms of hypocalcemia. Teaching:

Produced by ovaries after ovulation in non-pregnant women and placenta & corpus luteum (pg) Maintain endometrial lining, when levels drop -> menses Pregnancy-> no drop in progesterone, trophoblast makes hCG -> corpus luteum production of progesterone Prevents uterine contractions Slows peristalsis, constipation May suppress the woman's immune response Low progesterone: high risk of pregnancy loss Support fertility to get pg, stay pg During pg: low doses High doses: teratogenic Prematurity prevention: 17P Birth control: no endometrial lining may cause spotting (as lining erodes) Treat dysfunctional uterine bleeding (heavy) Adjunct in HRT estrogen replacement, as a protection against cancer