Previous changes

February 2025 — reviewed. A literature search was conducted in October 2024 to identify evidence-based guidelines, UK policy, systematic reviews, and key randomized controlled trials published since the last revision of this topic. No changes to clinical recommendations have been made.

June 2023 — minor update. The dosing regimen of enoxaparin has been updated in line with the manufacturer's summary of product characteristics (SPC). 

February 2022 — minor update. Acute generalized exanthematous pustulosis has been added as a potential adverse effect of enoxaparin. 

November 2020 — minor update. A typographical error has been corrected.

October 2020 — minor update. The contraindications of dalteparin have been updated in line with the manufacturer's revised SPC.

March 2020 — minor update. The management section has been updated in line with the updated National Institute for Health and Care Excellence (NICE) guideline Venous thromboembolic diseases: diagnosis, management and thrombophilia testing [NICE, 2020]. 

November 2019 to January 2020 — reviewed. A literature search was conducted in November 2019 to identify evidence-based guidelines, UK policy, systematic reviews, and key randomized controlled trials (RCTs) published since the last revision of this topic. 

September 2018 — minor update. Details of a randomized placebo-controlled trial that informed the update to the NICE guideline CG144 have been added to the Basis for recommendation section for the section on Follow up for DVT.

January 2018 — minor update. The recommendation on the use of elastic graduated compression stockings to prevent post-thrombotic syndrome (PTS) or venous thromboembolism recurrence after a proximal deep vein thrombosis (DVT) has been updated in line with updates to NICE guideline CG144.

December 2013 — minor update. Duplicate text deleted. Reference to prescriptions in the CKS topic on Compression stockings has been removed.

April 2013 — reviewed. A literature search was conducted in March 2013 to identify evidence-based guidelines, UK policy, systematic reviews, and key RCTs published since the last revision of the topic. Based on the new NICE guideline Venous thromboembolic diseases: the management of venous thromboembolic diseases and the role of thrombophilia testing, the recommendations for the management of suspected DVT have been revised to include the option of giving an interim 24-hour dose of parenteral anticoagulant if a proximal leg vein ultrasound scan cannot be carried out within 4 hours of being requested. 

September 2011 — minor update. All references to the British Committee for Standards in Haematology (BCSH) guideline on oral anticoagulation with warfarin have been updated to reflect the latest guideline. 

June 2010 — minor update. The recommendation on the class of compression stockings for preventing DVT or PTS has been updated.

January 2010 — minor update. The Basis for recommendation section for section on Management of suspected DVT has been updated to clarify why CKS recommends using the Wells Clinical Prediction Rule in preference to other clinical prediction rules (when D-dimer testing is available in primary care). 

December 2008 to March 2009 — converted from CKS guidance to CKS topic structure. The evidence base has been reviewed in detail, and recommendations are more clearly justified and transparently linked to the supporting evidence. There are no major changes to the recommendations.

June 2007 — updated to include a link to the recent Patient Safety Alert from the National Patient Safety Agency (NPSA) on actions that can make anticoagulant therapy safer. The BCSH's advice on managing people on oral anticoagulants requiring dental surgery was also included. Advice on managing interactions with warfarin was reformatted.

July 2006 — minor update to include advice from the Commission on Human Medicines (CHM) regarding the potential interaction between warfarin and glucosamine. 

October to December 2005 — reviewed. Validated in March 2006 and issued in May 2006.

July 2005 — minor update to include prescribing information for compression stockings. 

July 2002 — reviewed. A section on Advice on risk of travel-related deep vein thrombosis was added. Validated in October 2002 and issued in December 2002.

February 2001 — reviewed to incorporate the recommendations of the Scottish Intercollegiate Guidelines Network (SIGN) guideline Antithrombotic Therapy (1999).

February 1999 — written. Validated in April 1999 and issued in August 1999.

New evidence

Evidence-based guidelines

No new evidence-based guidelines since 1 October 2024.

HTAs (Health Technology Assessments)

No new HTAs since 1 October 2024.

Economic appraisals

No new economic appraisals relevant to England since 1 October 2024.

Systematic reviews and meta-analyses

No new systematic reviews or meta-analysis which reach the CKS threshold for inclusion since 1 October 2024.

Primary evidence

No new primary evidence which reaches the CKS threshold for inclusion published since 1 October 2024.

New policies

No new national policies or guidelines since 1 October 2024.

New safety alerts

No new safety alerts since 1 October 2024.

Changes in product availability

No changes in product availability since 1 October 2024.

Basis for recommendation

These recommendations are based on the National Institute for Health and Care Excellence (NICE) guideline Venous thromboembolic diseases: diagnosis, management and thrombophilia testing [NICE, 2023], the Scottish Intercollegiate Guidelines Network (SIGN) guideline Prevention and management of venous thromboembolism [SIGN, 2014], and expert opinion in review articles Deep vein thrombosis and pulmonary embolism [Di Nisio, 2016], Deep vein thrombosis [Stubbs, 2018], and Deep vein thrombosis [BMJ, 2024].

Basis for recommendation

This information is based on expert opinion in review articles Does this patient have deep vein thrombosis? [Anand et al, 1998], ABC of arterial and venous disease: swollen lower limb-1: general assessment and deep vein thrombosis [Gorman, 2000], Diagnosis, investigation, and management of deep vein thrombosis [Tovey, 2003], Deep vein thrombosis [BMJ, 2024].   

How should I manage a person with suspected deep vein thrombosis?

• If deep vein thrombosis (DVT) is suspected in a woman who is pregnant or in the postpartum period (within the past 6 weeks), arrange immediate referral for same-day assessment and management. 
• For all other people with suspected DVT, use the two-level DVT Wells score to assess the probability of DVT: 
  • Score one point for each of the following:
    • Active cancer (treatment ongoing, within the last 6 months, or palliative).
    • Paralysis, paresis, or recent plaster immobilization of the legs.
    • Recently bedridden for 3 days or more, or major surgery within the last 12 weeks requiring general or regional anaesthesia. 
    • Localized tenderness along the distribution of the deep venous system (such as the back of the calf).
    • Entire leg is swollen.
    • Calf swelling at least 3 cm larger than the asymptomatic leg.
    • Pitting oedema confined to the symptomatic leg.
    • Collateral superficial veins (non-varicose).
    • Previously documented DVT.
  • Subtract two points if an alternative cause is considered at least as likely as DVT.
  • The risk of DVT is likely if the score is two points or more and unlikely if the score is one point or less.
• If DVT is likely (Wells score 2 points or more), offer a proximal leg vein ultrasound scan with the result available within 4 hours if possible.
  • If the scan cannot be carried out within 4 hours of being requested, offer a D-dimer test, then interim therapeutic anticoagulation and a proximal leg vein ultrasound scan with the result available within 24 hours. 
• If DVT is unlikely (Wells score 1 point or less), offer a D-dimer test with the result available within 4 hours if possible. If the D-dimer result cannot be obtained within 4 hours, offer interim therapeutic anticoagulation while awaiting the result.
  • If the D-dimer test is positive, offer a proximal leg vein ultrasound scan with the result available within 4 hours. 
    • If the result cannot be obtained within 4 hours, offer interim therapeutic anticoagulation and a proximal leg vein ultrasound scan with the result available within 24 hours. 
  • If the D-dimer test is negative:
    • Stop interim therapeutic anticoagulation.
    • Consider an alternative diagnosis. 
    • Advise the person that it is unlikely they have DVT, but they should be aware of the signs and symptoms of DVT and seek medical help if symptoms worsen or they experience chest pain or breathing difficulties.
• If interim therapeutic anticoagulation is indicated:
  • Offer apixaban or rivaroxaban first-line, considering comorbidities, contraindications, the person's preferences, and local protocols. 
  • If apixaban or rivaroxaban are unsuitable, consider:
    • Low molecular weight heparin (LMWH) for at least 5 days, followed by dabigatran or edoxaban, or
    • LMWH alongside a vitamin K antagonist (warfarin) for at least 5 days.
  • For prescribing information on anticoagulants, see the sections on Oral anticoagulants and Parenteral anticoagulants.
  • The National Institute for Health and Care Excellence (NICE) has produced a visual summary of the recommendations on anticoagulation treatment for DVT, which includes anticoagulation options for people with renal impairment, active cancer, or antiphospholipid syndrome. 
• When using interim therapeutic anticoagulation:
  • Perform baseline blood tests, including full blood count, renal and hepatic function, prothrombin time (PT), and activated partial thromboplastin time (APTT). 
  • Do not wait for the results of baseline blood tests before starting anticoagulation treatment. 
  • Review and, if necessary, act on the results of baseline blood tests within 24 hours of starting interim therapeutic anticoagulation. 

How should I manage a person following hospital treatment for confirmed deep vein thrombosis?

After hospital treatment, people with confirmed deep vein thrombosis (DVT) will be offered maintenance anticoagulation treatment (if no contraindications) to prevent early recurrences. The treatment is usually continued for at least 3 months; however, the duration may be longer if the DVT was unprovoked (no obvious, transient risk factor identified) and the risk of recurrence outweighs the risk of major bleeding.

• Continue prescribing and monitoring maintenance anticoagulation treatment.
  • The anticoagulant effect of warfarin is measured as the international normalized ratio (INR).
  • Direct oral anticoagulants (such as apixaban) do not require INR monitoring, but regular follow up (at 1 month and then at least annually) is recommended to check treatment compliance, monitor for adverse effects (such as bleeding), and assess ongoing suitability.
  • For more information, see the CKS topic on Anticoagulation – oral.
• Give verbal and written information on: 
  
  • The recommended dose and duration of anticoagulant treatment.
  • Adverse effects, drug interactions, and monitoring requirements.
  • What to do if they are planning a pregnancy or become pregnant. 
  • How anticoagulation treatment can affect dental treatment and activities such as sports.
  • The risks associated with long-haul travel. For more information, see the section on Recent DVT in the CKS topic on DVT prevention for travellers.
  • When and how to seek medical help (for example, if there are signs and symptoms of bleeding or recurrent DVT).
  • The importance of carrying an 'anticoagulant alert card' at all times. 
• Manage modifiable risk factors for DVT, such as obesity. For more information, see the CKS topic on Obesity.
• Ensure that people with unprovoked DVT are:
  • Investigated for undiagnosed cancer. For more information, see the section on Investigations for cancer.
  • Offered thrombophilia testing (where appropriate). For more information, see the section on Thrombophilia testing.
• Do not offer graduated elastic compression stockings (ECS) to prevent recurrence of post-thrombotic syndrome or venous thromboembolism after a proximal DVT.
  • This recommendation does not cover the use of ECS for managing leg symptoms after DVT. 
  • If ECS are offered to manage leg symptoms after a DVT, explain how to apply and use them, how long they should be worn, and when they should be replaced.
    • For more information, see the section on Compression stockings in the CKS topic on DVT prevention for travellers.

What should I be aware of when prescribing dalteparin?

• Dalteparin is contraindicated in people with [EMC, 2023] [BNF, 2025]:
  • A history of confirmed or suspected immunologically mediated heparin-induced thrombocytopenia (type II).
  • Acute bacterial endocarditis.
  • Haemophilia or other haemorrhagic disorders.
  • Mechanical prosthetic heart valve.
  • Major trauma, active clinically significant bleeding, or conditions with a high risk of bleeding, such as:
    • Acute gastroduodenal ulcer.
    • Cerebral haemorrhage.
    • Known haemorrhagic diathesis.
    • Recent surgery (or injury) to the central nervous system, eyes, and ears.
• Dalteparin should be used with caution in [EMC, 2023] [BNF, 2025]:
  • Older people (especially 80 years and older) — increased risk for bleeding complications within the therapeutic dosage ranges.
  • People with conditions with an increased risk of bleeding complications, for example:
    • Following surgery or trauma.
    • Severe liver or renal failure.
    • Thrombocytopenia or defective platelet function.
    • Uncontrolled hypertension.
    • Hypertensive or diabetic retinopathy.
    • Concurrent anticoagulant/antiplatelet treatment.
• Dalteparin should be administered subcutaneously.
  • The recommended dosages for the treatment of deep vein thrombosis in adults are [BNF, 2025]: 
    • Body weight less than 46 kg — 7500 units once daily.
    • Body weight 46–56 kg — 10,000 units once daily.
    • Body weight 57–68 kg — 12,500 units once daily.
    • Body weight 69–82 kg — 15,000 units once daily.
    • Body weight 83 kg and over — 18,000 units once daily.
• For detailed information on prescribing dalteparin, see the British National Formulary and the Summary of Product Characteristics (listed in the electronic Medicines Compendium).

What should I be aware of when prescribing enoxaparin?

• Enoxaparin is contraindicated in people with [EMC, 2022a] [BNF, 2025]: 
  • History of immune-mediated heparin-induced thrombocytopenia (HIT) within the past 100 days or in the presence of circulating antibodies.
  • Acute bacterial endocarditis.
  • Haemophilia or other haemorrhagic disorders.
  • Mechanical prosthetic heart valve.
  • End-stage renal disease (creatinine clearance [CrCl] less than 15 mL/minute).
  • Major trauma, active clinically significant bleeding, or conditions with a high risk of bleeding, such as:
    • Recent haemorrhagic stroke.
    • Active gastrointestinal ulcer.
    • Presence of malignant neoplasm at high risk of bleeding.
    • Recent brain, spinal, or ophthalmic surgery.
    • Known or suspected oesophageal varices.
    • Arteriovenous malformations.
    • Vascular aneurysms.
    • Major intraspinal or intracerebral vascular abnormalities.
• Enoxaparin should be used with caution in [EMC, 2022a] [BNF, 2025]:
  
  • People with a history (more than 100 days) of HIT without circulating antibodies — the decision to use enoxaparin must be made only after carefully considering risks, benefits, and non-heparin alternative treatments.
  • Older people (especially 80 years and older) — may be at an increased risk of bleeding complications with therapeutic dosage ranges. 
  • Obesity — increased risk of thromboembolism.
  • People with conditions with an increased risk of bleeding, such as:
    • Impaired haemostasis.
    • History of peptic ulcer.
    • Recent ischemic stroke.
    • Severe arterial hypertension.
    • Recent diabetic retinopathy.
    • Hepatic impairment.
    • Severe renal impairment (CrCl 15–30 mL/minute) — a dosage adjustment is recommended.
    • Low body weight (less than 45 kg in women and less than 57 kg in men) — increased risk of bleeding due to increased exposure to enoxaparin.
    • Concurrent anticoagulant/antiplatelet treatment — concurrent treatment should be avoided or carefully monitored.
• Enoxaparin should be administered subcutaneously.
  • The recommended dosages for the treatment of deep vein thrombosis in adults are [EMC, 2022a]:
    • For uncomplicated people with a low risk of recurrence — 150 IU/kg (1.5 mg/kg) once daily.
    • For people with risk factors such as obesity, cancer, recurrent venous thromboembolism, or proximal (vena iliaca) thrombosis — 100 IU/kg (1 mg/kg) every 12 hours. 
    • For people with severe renal impairment (CrCl 15–30 mL/minute) — 100 IU/kg (1 mg/kg) once daily.
• For detailed information on prescribing enoxaparin, see the British National Formulary and the Summary of Product Characteristics (listed in the electronic Medicines Compendium).

What should I be aware of when prescribing tinzaparin?

• Tinzaparin is contraindicated in people with [EMC, 2022b] [BNF, 2025]:
  
  • Current or history of immune-mediated heparin-induced thrombocytopenia (type II).
  • Acute bacterial endocarditis.
  • Haemophilia or other haemorrhagic disorders.
  • Mechanical prosthetic heart valve.
  • Major trauma, active major bleeding, or conditions with a high risk of major bleeding, such as recent haemorrhagic stroke, spinal or ophthalmic surgery, or gastrointestinal ulcer. 
• Tinzaparin should be used with caution in [EMC, 2022b] [BNF, 2025]:
  • Older people — more likely to have reduced renal function.
  • People with conditions with an increased risk of bleeding complications, such as:
    • Severe hypertension.
    • Severe renal impairment (creatinine clearance less than 30 mL/minute) — monitoring of anti-Factor Xa is recommended.
• Tinzaparin should be administered subcutaneously.
  • The recommended dosage for the treatment of deep vein thrombosis is 175 units per kg once daily [EMC, 2022b]. 
• For detailed information on prescribing tinzaparin, see the British National Formulary and the Summary of Product Characteristics (listed in the electronic Medicines Compendium).

What issues should I be aware of when prescribing fondaparinux?

• Fondaparinux is contraindicated in people with [BNF, 2025; EMC, 2025]:
  • Active clinically significant bleeding.
  • Acute bacterial endocarditis.
  • Severe renal impairment (creatinine clearance less than 30 mL/min) — the risk of bleeding increases with increasing renal impairment.
• Fondaparinux should be used with caution in [BNF, 2025; EMC, 2025]:
  
  • Older people — as renal function declines with age, older people may have reduced fondaparinux elimination, leading to higher exposure and increased bleeding risk.
  • People who have undergone recent surgery (less than 3 days) and only once surgical haemostasis has been established.
  • People with conditions with an increased risk of bleeding complications, such as:
    • Congenital or acquired bleeding disorders.
    • Active ulcerative gastrointestinal disease.
    • Recent intracranial haemorrhage.
    • Moderate renal impairment (CrCl 30–50 mL/min).
    • Severe hepatic impairment.
  • People with:
    • Low body weight (less than 50 kg) — limited clinical experience. Fondaparinux should be used with caution at a daily dose of 5 mg in this population.
    • High body weight (over 100 kg) — limited clinical experience.
    • History of heparin-induced thrombocytopenia (HIT) — the efficacy and safety of fondaparinux have not been formally studied in people with HIT type II. 
    • Latex sensitivity — the needle shield of the pre-filled syringe contains dry natural latex rubber that can potentially cause allergic reactions in latex-sensitive people.
• Fondaparinux should be administered subcutaneously.
  • The recommended dosages for the treatment of deep vein thrombosis are [BNF, 2025; EMC, 2025]:
    • Body weight less than 50 kg — 5 mg every 24 hours.
    • Body weight 50–100 kg — 7.5 mg every 24 hours.
    • Body weight over 100 kg — 10 mg every 24 hours.
• For detailed information on prescribing fondaparinux, see the British National Formulary and the Summary of Product Characteristics (listed in the electronic Medicines Compendium).