dabigatran

dabigatran

(da-bye-gat-ran) ,

Pradaxa

(trade name)

Classification

Therapeutic: anticoagulants
Pharmacologic: thrombin inhibitors

Pregnancy Category: C

Indications

To reduce the risk of stroke/systemic embolization associated with nonvalvular atrial fibrillation.

Action

Acts as a direct inhibitor of thrombin.

Therapeutic effects

Lowered risk of thrombotic sequelae (stroke and systemic embolization) of nonvalvular atrial fibrillation.

Pharmacokinetics

Absorption: 3–7% absorbed following oral administration.

Distribution: Unknown.

Metabolism and Excretion: Of the amount absorbed, mostly excreted by kidneys (80%); 86% of ingested dose is eliminated in feces due to poor bioavailability.

Half-life: 12–17 hr.

Time/action profile (effects on coagulation)

ROUTE	ONSET	PEAK	DURATION
PO	within hours	unknown	2 days†

†Following discontinuation, 3–5 days in renal impairment.

Contraindications/Precautions

Contraindicated in: Hypersensitivity;Active pathological bleeding;Concurrent use of P-glycoprotein (P-gp) inducers;Prosthetic heart valves (mechanical or bioprosthetic)

Use Cautiously in: Concurrent medications/pre-existing conditions that ↑ bleeding risk (other anticoagulants, antiplatelet agents, antifibrinolytics, heparins, chronic NSAID use, labor and delivery);Renal impairmentSurgical procedures (discontinue 1–2 days prior if CCr ≥50 mL/min or 3–4 days prior if CCr <50 mL/min; Geriatric: ↑ risk of bleeding; Lactation: Use cautiously during breast feeding; Pediatric: Safety and effectiveness not established.

Adverse Reactions/Side Effects

Gastrointestinal

• abdominal pain (most frequent)
• diarrhea (most frequent)
• dyspepsia (most frequent)
• gastritis (most frequent)
• nausea

Hematologic

• bleeding
• thrombocytopenia

Miscellaneous

• angioedema (life-threatening)
• hypersensitivity reactions including anaphylaxis (life-threatening)

Interactions

Drug-Drug interaction

Concurrent use of other anticoagulants, antiplatelet agents, antifibrinolytics, heparins, prasugrel, clopidogrel, or chronic use of NSAIDs ↑ risk of bleeding.Concurrent use of P-gp inducers including rifampin ↓ levels and effectiveness; avoid concurrent use.P-gp inhibitors, including dronedarone and ketoconazole (systemic), may ↑ levels and the risk of bleeding; concomitant use should be avoided in patients with CCr 15–30 mL/min.

Route/Dosage

Oral (Adults) 150 mg twice daily.

Renal Impairment

Oral (Adults) CCr 30–50 mL/min and taking dronedarone or systemic ketoconazole—75 mg twice daily; CCr 15–30 mL/min—75 mg twice daily; CCr 15–30 mL/min and taking P-gp inhibitor—Avoid concomitant use; CCr <15 mL/min—Not recommended.

Availability

Capsules: 75 mg, 110 mg, 150 mg

Nursing implications

Nursing assessment

• Assess for symptoms of stroke or peripheral vascular disease periodically during therapy.
• Assess for symptoms of bleeding and blood loss; may be fatal.
• Lab Test Considerations: Use aPTT or ECT, not INR, to assess anticoagulant activity, if needed.
  • Monitor renal function prior to and periodically during therapy. Patients with renal impairment may require dose reduction or discontinuation.

Potential Nursing Diagnoses

Activity intolerance

Implementation

• When converting from warfarin, discontinue warfarin and start dabigatran when INR is <2.0.
• When converting from dabigatran to warfarin, adjust starting time based on creatinine clearance. For CCr >50 mL/min, start warfarin 3 days before discontinuing dabigatran. For CCr 31–50 mL/min, start warfarin 2 days before discontinuing dabigatran. For CCr 15–30 mL/min, start warfarin 1 day before discontinuing dabigatran. For CCr <15 mL/min, no recommendations can be made. INR will better reflect warfarin's effect after dabigatran has been stopped for at least 2 days.
• When converting from parenteral anticoagulants, start dabigatran up to 2 hr before next dose of parenteral drug is due or at time of discontinuation of parenteral therapy.
• When converting to dabigatran from parenteral anticoagulants, wait 12 hrs (CCr ≥30 mL/min) or 24 hr (CCr <30 mL/min) after last dose of dabigatran before initiating parenteral anticoagulant therapy.
• For surgery, discontinue dabigatran 1–2 days (CrCL ≥50 mL/min) or 3–5 days (CCr <50 mL/min) before invasive or surgical procedures; consider longer times for major surgery, spinal puncture, or placement of a spinal or epidural catheter. If surgery cannot be delayed, bleeding risk is ↑. Assess bleeding risk with ecarin clotting time (ECT) or a PTT if ECT is not available.
• Oral: Administer twice daily without regard to food. Swallow capsule whole; do not open, crush, or chew; may result in increased exposure.
  • If dabigatran is discontinued, consider starting another anticoagulant; discontinuation of dabigatran increases risk of thrombotic events.

Patient/Family Teaching

• Instruct patient to take dabigatran as directed. Take missed doses as soon as remembered within 6 hr. If <6 hr until next dose, skip dose and take next dose when scheduled; do not double doses. Do not discontinue without consulting health care professional. If temporarily discontinued, restart as soon as possible. Store dabigatran at room temperature. After opening bottle, use within 4 mo; discard unused dabigatran after 4 mo.
• Inform patient that they may bleed more easily or longer than usual. Advise patient to notify health care professional immediately if signs of bleeding (unusual bruising; pink or brown urine; red or black, tarry stools; coughing up blood; vomiting blood; pain or swelling in a joint; headache; dizziness; weakness; recurring nose bleeds; unusual bleeding from gums; heavier than normal menstrual bleeding; dyspepsia; abdominal pain; epigastric pain) occur..
• Advise patient to notify health care professional of medication regimen prior to treatment or surgery.
• Instruct patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and consult health care professional before taking any new medications.
• Advise female patient to notify health care professional if pregnancy is planned or suspected or if breast feeding.

Evaluation/Desired Outcomes

• Reduction in the risk of stroke and systemic embolism.