Clinical Medications WorksheetsGeneric Namedigoxin

Trade NameLanoxin

Classificationantiarrhythmics, inotropics

Dose0.25mg0.125mg

RoutePOPO

Time/frequencyQ Sun., Tue., Thurs.Q Mon., Wed., Fri., Sat.

Peak2-8 hr

Onset30-120 min

Duration2-4 days

Normal dosage rangeDigitalizing dose--0.75-1.5 mg given as 50% of the dose initially and one quarter of the initial dose in each of 2 subsequent doses at 6-12 hr intervals. Maintenance dose--0.125-0.5 mg/day as tablets or 0.350-0.5 mg/day as gelatin capsules, depending on patient's lean body weight, renal function, and serum level.(Geriatric Patients): Daily dosage should not exceed 0.125 mg except when treating atrial fibrillation.Digoxin has a narrow therapeutic range (0.5-2 ng/ml). Have second practitioner independently check original order and dose calculations. Monitor therapeutic drug levels.

Why is your patient getting this medicationTreatment of CHF

For IV meds, compatibility with IV drips and/or solutionsN/A

Mechanism of action and indicationsIncreases the force of myocardial contraction. Prolongs refractory period of the AV node. Decreases conduction through the SA and AV nodes. Digoxin inhibits the Na-K-ATPase membrane pump, resulting in an increase in intracellular sodium and calcium concentrations. Increased intracellular concentrations of calcium may promote activation of contractile proteins (e.g., actin, myosin). Digoxin also acts on the electrical activity of the heart, increasing the slope of phase 4 depolarization, shortening the action potential duration, and decreasing the maximal diastolic potential.

Nursing Implications (what to focus on) Contraindications/warnings/interactionsHypersensitivity, uncontrolled ventricular arrhythmias, AV block, Idiopathic hypertophic subaortic stenosis, constrictive pericarditis. Use cautiously in: electrolyte abnormalities (hypokalemia, hypercalcemia, and hypomagnesemia may predispose toxicity), hypothyroidism, geriatric patients (very sensitive to toxic effects, dose adjustments required for age-related decrease in renal function and body weight), MI, renal impairment, obesity (dose should be based on ideal body weight). Common side effectsFatigue, ARRYTHMIAS, bradycardia, anorexia, nausea, vomiting.

Interactions with other patient drugs, OTC or herbal medicines (ask patient specifically)Demadex: Although diuretics and digitalis glycosides are frequently and appropriately used together, diuretic-induced hypokalemia and hypomagnesemia may predispose patients on digitalis to arrhythmias.Fludrocortisone, hydrocortisone: Systemically administered corticosteroids may induce hypokalemia and possibly increase the risk of digoxin toxicity. In addition, corticosteroid-induced sodium and water retention can result in edema leading to heart failure. These effects may be more common with the natural corticosteroids (cortisone, hydrocortisone) which have greater mineralocorticoid activity.Synthroid: The clearance of or sensitivity to digitalis glycosides may be increased in previously hypothyroid patients when a euthyroid state is achieved after the addition of thyroid hormones.Coreg: Concomitant use of digitalis glycosides and beta-blockers including carvedilol may increase the risk of bradycardia. These agents slow atrioventricular conduction and decrease heart rate, hence they may have additive cardiac effects during coadministration. Pharmacokinetically, carvedilol has been shown to modestly increase the systemic bioavailability of digoxin. The mechanism may involve enhanced absorption as well as reduced renal excretion of digoxin due to inhibition of intestinal and renal P-glycoprotein

Lab value alterations caused by medicineEvaluate serum electrolyte levels (especially potassium, magnesium, and calcium) and renal and hepatic functions periodically during therapy. Notify physician or other health care professional before giving dose if patient is hypokalemic. Hypokalemia, hypomagnesemia, or hypercalcemia may make the patient more susceptible to digitalis toxicity. Older adults may be toxic even when serum concentrations are within normal range; assess for clinical symptoms of toxicity even when serum levels are normal.Be sure to teach the patient the following about this medicationInstruct patient to take medication as directed, at the same time each day. Missed doses should be taken within 12 hr of scheduled dose or not taken at all. Do not double doses. Consult health care professional if doses for 2 or more days are missed. Do not discontinue medication without consulting health care professional. Teach patient to take pulse and to contact health care professional before taking medication if pulse rate is <60 or >100. Review signs and symptoms of digitalis toxicity with patient and family. Advise patient to notify health care professional immediately if these or symptoms of CHF occur. Inform patient that these symptoms may be mistaken for those of colds or flu. Instruct patient to keep digoxin tablets in their original container and not to mix in pill boxes with other medications; they may look similar to and may be mistaken for other medications. Advise patient that sharing of this medication can be dangerous. Caution patient to avoid concurrent use of OTC and herbal products without consulting health care professional. Advise patient to avoid taking antacids or

Lanoxin (digoxin)

efflux transporter by carvedilol. ASA: Nonsteroidal anti-inflammatory drugs (NSAIDs) may increase plasma digoxin concentrations and half-life. The exact mechanism is unknown, but may be related to reduced renal clearance of digoxin. Data have been conflicting. The interaction has been reported with indomethacin and ibuprofen, but data for other NSAIDs are not available.Reglan: Digoxin serum concentrations may be reduced during concomitant therapy with metoclopramide. The proposed mechanism is metoclopramide-induced stimulation of gastric motility, which may decrease digoxin absorption. Rapidly dissolving preparations such as digoxin solution in capsules do not appear to be affected. Patients should be advised to notify their physicians if they experience worsening of their heart symptoms.Proventil, Xopenex: Administration of a single oral dose of albuterol has resulted in a 22% decrease in serum digoxin levels and a 14% decrease in serum potassium. The mechanism is unknown. Serum digoxin levels and clinical response should be monitored during concurrent administration with albuterol. Dosages should be adjusted as necessary.Protonix: Proton pump inhibitors may increase the bioavailability of digoxin. The proposed mechanism is a pH-dependent increase in gastrointestinal absorption of digoxin. The clinical significance of this effect is unknown. In patients treated with proton pump inhibitors, the possibility of an enhanced pharmacologic response to digoxin should be considered. Patients should be closely monitored for development of toxicity, particularly those with digoxin levels in the upper range of normal. Patients should be be advised to notify their physician if they experience nausea, anorexia, visual changes, slow pulse, or irregular heartbeats.

antidiarrheals within 2 hr of digoxin. Advise patient to notify health care professional of this medication regimen before treatment. Patients taking digoxin should carry identification describing disease process and medication regimen at all times. Review fall prevention strategies with older adults and their families. Emphasize the importance of routine follow-up exams to determine effectiveness and to monitor for toxicity.

Nursing Process- Assessment(Pre-administration assessment)Monitor apical pulse for 1 full min before administering. Monitor intake and output ratios and daily weights. Assess for peripheral edema, and auscultate lungs for rales/crackles throughout therapy. Before administering initial loading dose, determine whether patient has taken any digitalis preparations in the preceding 2-3 wk. Digoxin use has been associated with an increased risk of falls in the elderly. Assess for falls risk and implement prevention strategies per facility protocol.

AssessmentWhy would you hold or not give this med?S/S of toxicity: abdominal pain, anorexia, nausea, vomiting, visual disturbances, bradycardia, and other arrhythmias. Pulse rate is <60 bpm. Withhold drug and notify physician or health care professional immediately.

EvaluationCheck after givingDecrease in severity of CHF. Increase in cardiac output.

Lanoxin (digoxin)