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Low molecular weight heparin (LMWH) Pregnancy: Section 4.6: 'Pregnancy - Animal studies have not shown any evidence of teratogenic effects with the use of bemiparin (see section 5.3). For bemiparin, clinical data on exposed pregnancies are limited. However, caution should be exercised when prescribing to pregnant women. It is unknown whether bemiparin crosses placental barrier. Breastfeeding - Insufficient information is available as to whether bemiparin passes into breast milk. Therefore, where it is necessary for lactating mothers to receive Zibor, they should be advised to avoid breastfeeding.'

Bemiparin sodium

Brand names: Zibor

Bemiparin sodium is a second-generation low molecular weight heparin used for prophylaxis and treatment of venous thromboembolism.

Adult dose

Dose: Prevention of thromboembolic disease in adults undergoing orthopaedic surgery with high risk of venous thromboembolism: 3,500 IU anti-Xa subcutaneously on the day of surgery (2 hours before or 6 hours after surgery), then 3,500 IU anti-Xa subcutaneously every 24 hours on subsequent days.
Route: Subcutaneous
Frequency: Once every 24 hours (first dose 2 hours before or 6 hours after surgery)
Strength (SPC section 2): 3500 IU (anti Factor Xa) per 0.2 ml pre-filled syringe (equivalent to 17500 IU per millilitre); potency is in International anti-Factor Xa units (IU). WARNING in section 4.2: the different low molecular weight heparins are not necessarily equivalent, so the dosage regimen and method of use specific to each product must be followed. Duration (section 4.2): prophylactic treatment must be followed in accordance with the physician's opinion during the period of risk or until the patient is mobilised; as a general rule it is considered necessary to maintain prophylaxis for at least 7-10 days after the surgical procedure and until the risk of thromboembolic disease has decreased. SCOPE: the SPC licenses this product only for (1) prevention of thromboembolic disease in orthopaedic surgery patients and (2) prevention of clotting in the extracorporeal circuit during haemodialysis (section 4.1). It gives NO dose for general-surgical or medical VTE prophylaxis and NO treatment-dose regimen for established VTE, so none is written here. Haemodialysis (not a subcutaneous dose): for repeated haemodialysis of no longer than 4 hours with no risk of bleeding, a single bolus is injected into the arterial line at the start of the session - 2,500 IU for patients weighing less than 60 kg and 3,500 IU for patients weighing more than 60 kg (section 4.2). Do not administer by the intramuscular route (section 4.4). Injection technique (section 4.2): pre-filled syringes are ready for immediate use and must not be purged before injection; inject into the subcutaneous tissue of the anterolateral or posterolateral abdominal waist, alternating left and right sides, with the needle fully inserted perpendicularly into a held skin fold; do not rub the site. Neuraxial anaesthesia (section 4.4): the subsequent dose should not be given until at least four hours after removal of an epidural or spinal catheter and should be delayed until the surgical procedure is completed. The safety and efficacy of Zibor in children has not been established (section 4.2).

Dose adjustments

Renal

SPC 4.2 (orthopaedic surgery prophylaxis): mild or moderate renal insufficiency (creatinine clearance 30-80 ml/min) - no dose adjustment is necessary, but close monitoring is recommended. Severe renal insufficiency (creatinine clearance <30 ml/min) could influence the pharmacokinetics; assess individual bleeding and thrombotic risks; in some cases the dose may need to be adjusted and, based on limited pharmacokinetic data, a dose reduction up to 2,500 IU anti-Xa s.c. once daily could be recommended, with close monitoring; measurement of peak anti-Xa levels at about 4 hours post-dose should be considered.

Hepatic

SPC 4.2: there are insufficient data to recommend a dose adjustment of bemiparin in patients with hepatic impairment. Contraindicated in severe impairment of liver or pancreatic function (section 4.3); caution in liver failure (section 4.4).

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via MHRA Products — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Hypersensitivity to the active substance or to any of the excipients (section 4.3)
  • Hypersensitivity to heparin or its derivatives, including other low molecular weight heparins, or substances of porcine origin (section 4.3)
  • History of confirmed or suspected immunologically mediated heparin-induced thrombocytopenia (HIT) (section 4.3)
  • Active haemorrhage or increased risk of bleeding due to impairment of haemostasis (section 4.3)
  • Severe impairment of liver or pancreatic function (section 4.3)
  • Injuries to or operations on the central nervous system, eyes and ears within the last 2 months (section 4.3)
  • Disseminated intravascular coagulation (DIC) attributable to heparin-induced thrombocytopenia (section 4.3)
  • Acute bacterial endocarditis and slow endocarditis (section 4.3)
  • Any organic lesion with high risk of bleeding, e.g. active peptic ulcer, haemorrhagic stroke, cerebral aneurysm or cerebral neoplasms (section 4.3)

Side effects

  • Haematoma and/or ecchymosis at the injection site (the most commonly reported adverse reaction; approximately 15% of patients); pain at the injection site (section 4.8)
  • Bleeding complications (skin, mucous membranes, wounds, gastro-intestinal tract, urogenital tract) which may cause haemorrhagic anaemia - common (section 4.8)
  • Mild and transient elevations of transaminases (ASAT, ALAT) and gamma-GT - common (section 4.8)
  • Mild and transient thrombocytopenia (HIT type I) - uncommon; severe thrombocytopenia (type II) - rare (sections 4.4, 4.8)
  • Cutaneous allergic reactions (urticaria, pruritus) - uncommon; anaphylactic reactions (nausea, vomiting, fever, dyspnoea, bronchospasm, glottis oedema, hypotension, urticaria, pruritus) - rare (section 4.8)
  • Cutaneous necrosis at the injection site - rare (sections 4.4, 4.8)
  • Epidural or spinal haematoma following epidural or spinal anaesthesia or lumbar puncture, resulting in prolonged or permanent paralysis - very rare with prophylactic heparin (section 4.4; also listed in section 4.8)
  • Hyperkalaemia - frequency not known; osteoporosis associated with long-term heparin treatment (sections 4.4, 4.8)

Interactions

  • Vitamin K antagonists and other anticoagulants, acetylsalicylic acid and other salicylates, NSAIDs, ticlopidine, clopidogrel and other platelet inhibitors, systemic glucocorticoids and dextran - concomitant use not advisable (increased bleeding risk); if unavoidable use careful clinical and laboratory monitoring (section 4.5)
  • Medicinal products that increase serum potassium - only under especially careful medical supervision (sections 4.4, 4.5)
  • Intravenous nitroglycerine - interaction with heparin (decreased efficacy) cannot be ruled out for bemiparin (section 4.5)
  • SPC states interaction information is derived from other LMWHs; bemiparin interactions have not been investigated (section 4.5)

Monitoring

  • Platelet counts before administration, on the first day of therapy, then regularly at 3 to 4 days and at the end of therapy; stop and use alternative therapy if a significantly reduced platelet count (30 to 50%) occurs with positive or unknown anti-platelet antibody tests (section 4.4)
  • Serum electrolytes (potassium) in patients at risk of hyperkalaemia before starting and regularly thereafter, particularly if treatment is prolonged beyond 7 days (section 4.4)
  • Close monitoring in mild or moderate renal impairment (creatinine clearance 30-80 ml/min); regular monitoring and consideration of peak anti-Xa level about 4 hours post-dose in severe renal impairment (sections 4.2, 4.4)
  • After epidural/spinal anaesthesia or lumbar puncture: frequent monitoring for signs of neurological impairment (back pain, sensory and motor deficits, bowel or bladder dysfunction) (section 4.4)

Clinical monograph

How it works

It potentiates antithrombin, producing predominantly anti-factor Xa activity with relatively little effect on thrombin, thereby inhibiting clot formation.

Prescribing in practice

  • The main risk is bleeding, so use with caution where bleeding risk is high and avoid in active major haemorrhage.
  • Dose is reduced in renal impairment because of accumulation, and it is given by subcutaneous injection.
  • Heparin-induced thrombocytopenia can occur, and it should be avoided in those with a history of it.

Monitoring

Routine anticoagulant monitoring is not usually required, but check platelet count and renal function, with anti-Xa levels considered in selected patients.

Counselling the patient

  • The injection is given under the skin and you can be taught to do this yourself.
  • Report any unusual bleeding or bruising.
  • Do not stop treatment early without medical advice.

Evidence & guidelines

Low molecular weight heparins such as bemiparin have a well-established evidence base for the prevention and treatment of venous thromboembolism.

Reference: NICE NG89; NG158; BSH; 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).

Related

Curated clinical cross-links plus same-class fallbacks.

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