Direct Oral Thrombin Inhibitor — VTE / AF Stroke Prevention Pregnancy: Women of childbearing potential should avoid pregnancy during treatment. There are limited data in pregnant women and animal studies have shown reproductive toxicity; dabigatran etexilate should not be used during pregnancy unless clearly necessary. Breast-feeding should be discontinued during treatment.

Dabigatran

Brand names: Pradaxa

Dabigatran etexilate is an oral direct thrombin inhibitor used to prevent stroke in non-valvular atrial fibrillation and to treat and prevent venous thromboembolism.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 300 mg dabigatran etexilate daily, taken as one 150 mg capsule twice daily — for prevention of stroke and systemic embolism in non-valvular AF (SPAF), and for treatment of DVT/PE and prevention of recurrent DVT/PE (the latter following at least 5 days of a parenteral anticoagulant)

Route: Oral — capsules swallowed whole with a glass of water, with or without food; patients must NOT open the capsule (increases bleeding risk)

Frequency: Twice daily

DOSE REDUCTION TO 220 mg DAILY (one 110 mg capsule twice daily) IS RECOMMENDED IN: patients aged 80 years or over, and patients receiving concomitant verapamil. DOSE REDUCTION FOR CONSIDERATION IN: patients aged 75-80 years (300 mg or 220 mg selected on individual thromboembolic vs bleeding risk); moderate renal impairment (CrCl 30-50 mL/min); gastritis, oesophagitis or gastro-oesophageal reflux; other patients at increased risk of bleeding. Note the SPC states the 220 mg regimen in DVT/PE is based on PK/PD analyses and has not been studied in that clinical setting. VTE PROPHYLAXIS AFTER ORTHOPAEDIC SURGERY (different regimen): a single 110 mg capsule 1-4 hours after completed surgery, then 220 mg once daily (two 110 mg capsules) from the first postoperative day — for 10 days after elective knee replacement and 28-35 days after elective hip replacement; reduced to a single 75 mg capsule on day of surgery then 150 mg once daily (two 75 mg capsules) in moderate renal impairment (CrCl 30-50 mL/min), with concomitant verapamil, amiodarone or quinidine, or age 75 or above. If haemostasis is not secured, delay initiation; if treatment is not started on the day of surgery, start with 2 capsules once daily. DURATION: SPAF — long term; DVT/PE — individualised, at least 3 months for transient risk factors, longer for permanent risk factors or idiopathic DVT/PE. MISSED DOSE (SPAF, DVT/PE): a forgotten dose may still be taken up to 6 hours before the next scheduled dose; from 6 hours before, omit it. Never double a dose. SWITCHING: to a parenteral anticoagulant — wait 12 hours after the last dose (24 hours in the orthopaedic-prophylaxis indication); from a parenteral anticoagulant — start dabigatran 0-2 hours before the next dose of the alternate therapy would be due, or at the time of discontinuation for continuous infusions such as IV unfractionated heparin; to a VKA — start the VKA 3 days before stopping dabigatran if CrCl 50 mL/min or more, or 2 days before if CrCl 30 to under 50 mL/min (INR unreliable until dabigatran has been stopped at least 2 days); from a VKA — stop the VKA and start dabigatran once INR is below 2.0. RENAL ASSESSMENT: calculate creatinine clearance by the Cockcroft-Gault method before starting, to exclude CrCl < 30 mL/min, and at least annually in mild-to-moderate renal impairment and in patients over 75. REVERSAL: idarucizumab is the specific reversal agent for adults; haemodialysis can remove dabigatran. PAEDIATRIC: no relevant use in SPAF or in orthopaedic VTE prophylaxis. For treatment and prevention of recurrent VTE in children, capsules may be used from 8 years of age in those able to swallow them whole; dosing is by weight AND age bands from SPC Table 4 — the numeric contents of Table 4 were NOT captured in this fetch, so no paediatric figures are recorded here. Paediatric renal function is assessed by eGFR (Schwartz formula) and dabigatran is contraindicated below 50 mL/min/1.73m2. Verify against the full SPC table and a children's formulary.

Dose adjustments

Renal

Contraindicated if CrCl < 30 mL/min in adults (eGFR < 50 mL/min/1.73m2 in children). No dose adjustment in mild renal impairment (CrCl 50 to 80 mL/min). In moderate renal impairment (CrCl 30-50 mL/min) the recommended SPAF/DVT/PE dose is still 300 mg daily as one 150 mg capsule twice daily, but a reduction to 220 mg daily (one 110 mg capsule twice daily) should be considered in patients at high bleeding risk. In the orthopaedic VTE-prophylaxis indication, moderate renal impairment requires the reduced regimen (75 mg on the day of surgery, then 150 mg once daily). With moderate renal impairment plus concomitant verapamil, consider reducing to 75 mg daily. Assess CrCl by Cockcroft-Gault before starting and at least annually thereafter in mild/moderate impairment and in patients over 75. (US label differs: CrCl 15 to 30 mL/min — 75 mg twice daily for non-valvular AF.)

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to dabigatran etexilate or to any of the excipients
Severe renal impairment (CrCl < 30 mL/min) in adults; eGFR < 50 mL/min/1.73m2 in paediatric patients
Active clinically significant bleeding
Any lesion or condition considered a significant risk factor for major bleeding — current or recent GI ulceration, malignant neoplasms at high risk of bleeding, recent brain or spinal injury, recent brain, spinal or ophthalmic surgery, recent intracranial haemorrhage, known or suspected oesophageal varices, arteriovenous malformations, vascular aneurysms, or major intraspinal/intracerebral vascular abnormalities
Concomitant treatment with any other anticoagulant (unfractionated heparin, LMWHs such as enoxaparin or dalteparin, heparin derivatives such as fondaparinux, or oral anticoagulants such as warfarin, rivaroxaban, apixaban) except when switching therapy, when UFH is used to keep a central venous or arterial catheter open, or when UFH is given during catheter ablation for AF
Hepatic impairment or liver disease expected to have any impact on survival
Concomitant treatment with the strong P-gp inhibitors systemic ketoconazole, ciclosporin, itraconazole, dronedarone, or the fixed-dose combination glecaprevir/pibrentasvir
Prosthetic heart valves requiring anticoagulant treatment (US label: mechanical prosthetic heart valve)

Side effects

Bleeding at any site — the most common adverse event; approximately 16.6% of AF patients on long-term treatment, 14.4% of adults treated for DVT/PE and 14% of short-term orthopaedic patients experienced bleeding, and major or severe bleeds may be disabling, life-threatening or fatal
Major gastrointestinal bleeding — higher rates than comparator, with increased risk in patients 75 years or older on 150 mg twice daily
Anaemia (common in AF patients) and decreased haemoglobin/haematocrit
Dyspepsia and other gastrointestinal symptoms — patients should be told to contact their doctor if these develop
Thrombocytopenia (uncommon to rare); neutropenia and agranulocytosis (frequency not known)
Drug hypersensitivity, rash, pruritus, and rarely anaphylactic reaction, angioedema, urticaria and bronchospasm

Interactions

Strong P-gp inhibitors (systemic ketoconazole, ciclosporin, itraconazole, dronedarone, glecaprevir/pibrentasvir) — contraindicated
Mild to moderate P-gp inhibitors — verapamil requires a dose reduction (and should be taken at the same time as dabigatran); amiodarone, quinidine and ticagrelor increase dabigatran plasma levels and are listed as bleeding risk factors (the UK SPC requires reduction with amiodarone/quinidine/verapamil in the orthopaedic-prophylaxis indication)
P-gp inducers (e.g. rifampicin) — reduce dabigatran exposure; avoid co-administration (US label)
Antiplatelet agents (aspirin, clopidogrel) and NSAIDs — increase bleeding risk, especially major gastrointestinal bleeding
SSRIs and SNRIs, and other medicinal products that impair haemostasis — increase bleeding risk
Neuraxial anaesthesia/spinal puncture — spinal/epidural haematoma risk

Clinical monograph

How it works

It is a prodrug converted to dabigatran, which directly and reversibly inhibits free and clot-bound thrombin (factor IIa), preventing conversion of fibrinogen to fibrin.

Prescribing in practice

It is substantially renally cleared, so renal function must be assessed before and during treatment and the drug avoided or dose-adjusted in significant impairment to limit bleeding risk.
Absorption depends on P-glycoprotein, so interactions with verapamil, dronedarone and inducers such as rifampicin are relevant, and dyspepsia is a common adverse effect.
A specific reversal agent, idarucizumab, is available for life-threatening bleeding or emergency surgery.

Monitoring

Check renal function at baseline and at least annually, more often in the elderly or when function may decline, and review for signs of bleeding rather than routine coagulation testing.

Counselling the patient

Swallow capsules whole and keep them in the original blister or bottle to protect from moisture.
Report any unusual or prolonged bleeding.
Do not miss doses, and carry an anticoagulant alert card.

Evidence & guidelines

The RE-LY trial demonstrated dabigatran was at least as effective as warfarin for stroke prevention in atrial fibrillation, supporting its NICE-recommended use.

Reference: RE-LY Trial; RE-COVER Trial; NICE TA327 (Dabigatran for VTE); Idarucizumab REVERSE-AD Trial; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways