Injectable anticoagulants

Key recommendation:

For a patient who is taking a prophylactic (low) dose of a low molecular weight heparin, treat without interrupting their anticoagulant medication.
(Conditional recommendation; very low certainty evidence) [new 2022]

Refer to Section 7 of the full guidance.

There is a lack of direct clinical evidence regarding the risk of bleeding complications for dental patients taking injectable anticoagulants, including the low molecular weight heparins (LMWHs: dalteparin [Fragmin], enoxaparin [Clexane] and tinzaparin [Innohep]).

Treatment doses of LMWHs are generally considered to be equivalent to treatment with warfarin (within therapeutic range) or DOACs. The risk of bleeding for patients taking LMWHs is dose dependent and so for patients taking a prophylactic (low) dose, the risk is likely to be lower than for a treatment dose and may be lower than for patients taking a VKA.

This recommendation only applies to patients on low prophylactic doses where the bleeding risk is likely to be lowest and is a conditional recommendation because of the uncertainty about bleeding risk for patients taking LMWHs who require dental treatment.

For patients on treatment doses, consultation with the patient’s prescribing clinician or specialist would usually be required to assess the likely impact of their medication and medical condition on their bleeding risk and establish the appropriate dental treatment management.

For a patient who is taking a low molecular weight heparin (LMWH) and requires dental treatment that is likely to cause bleeding, with either a low or higher risk of bleeding complications (see Bleeding risks for dental procedures):

    • For patients with renal impairment, or body weight <50kg or >100kg, the dose of LMWH is likely to have been adjusted and consultation with the prescribing clinician (e.g. specialist or general medical practitioner) may be required to confirm whether the patient is taking a prophylactic or treatment dose
  • If the patient is taking a treatment (higher) dose, or there is uncertainty about the dose they are taking, consult with the prescribing clinician (e.g. specialist or general medical practitioner) in order to assess the likely impact on bleeding risk for the dental procedure.
  • If the patient is taking a prophylactic (low) dose, treat according to the general advice for managing bleeding risk, without interrupting their anticoagulant.

In addition:

  • Consider limiting the initial treatment area (e.g. perform a single extraction or limit root surface debridement to 3 teeth, then assess bleeding before continuing).
  • For procedures with a higher risk of post-operative bleeding complications (see Bleeding risks for dental procedures), consider carrying out the treatments in a staged manner, where possible, over separate visits.
  • Use local haemostatic measures to achieve haemostasis. Strongly consider suturing and packing, taking into account all relevant patient factors (see Managing bleeding risk).

LMWHs are prescribed for relatively short periods of time following elective orthopaedic surgery (up to 6 weeks) and, where possible, dental treatment likely to cause bleeding should be delayed for these patients until they are no longer taking anticoagulants.

Like the DOACs, the LMWHs have a short onset of action and short half-lives. In relation to major surgery, typical advice is to interrupt LMWHs 24 hours before and so it would be reasonable to assume that dental treatment could proceed for a patient who has recently stopped taking a LMWH (24 hours or more previously) unless there are any other concerns.

Similarly, for patients given heparin or one of the LMWHs during kidney dialysis, where possible dental treatments likely to cause bleeding should be delayed until the following day.

The low molecular weight heparins (LMWHs), dalteparin (Fragmin), enoxaparin (Clexane) and tinzaparin (Innohep) are used for the prophylaxis and treatment of venous thromboembolism and are administered parenterally by subcutaneous injection rather than orally.

Although used in limited patient groups, they may be increasingly encountered in primary or secondary dental care settings. Patients taking LMWHs include:

  • pregnant women with indications for anticoagulation
  • patients with venous thrombosis with a background of cancer
  • short-term use in patients following orthopaedic or other surgery
  • care home residents with limited mobility and other risk factors may also be on LMWHs for thromboprophylaxis

LMWHs may be administered once or twice a day at either prophylactic or treatment (therapeutic) doses.

Lower doses are generally used for prophylaxis whereas treatment doses tend to be higher (see Licensed prophylactic and treatment doses of LMWHs). However, the doses can vary for individuals depending on weight and renal function and may be further adjusted by the patient’s specialist, based on measuring anti-Xa levels, to non-standard unlicensed doses for a given indication.

Consequently, there can be overlap between doses used for prophylaxis or treatment and advice from the prescriber of the patient’s LMWH might need to be sought to confirm the type of dose being taken.