Version October 2024
| VTE treatment | VTE prophylaxis | Product labeling on use in patients with a high BMI | |
| Enoxaparin* | Use standard treatment dosing (ie, 1 mg/kg every 12 hours based on TBW).¶ Once-daily dosing regimens of enoxaparin are not recommended.[1] | BMI 30 to 39 kg/m2: Use standard prophylaxis dosing (ie, 30 mg every 12 hours or 40 mg once daily).[2] Some experts use weight-based dosing (ie, 0.5 mg/kg based on TBW once or twice daily, depending upon level of VTE risk).Δ[3,4] BMI ≥40 kg/m2: Empirically increase standard prophylaxis dose by 30% (ie, from 30 mg every 12 hours to 40 mg every 12 hours).◊[2] Some experts use weight-based dosing (ie, 0.5 mg/kg based on TBW once or twice daily, depending upon level of VTE risk).Δ[3-7] High VTE-risk bariatric surgery with BMI ≤50 kg/m2: 40 mg every 12 hours.§[8,9] High VTE-risk bariatric surgery with BMI >50 kg/m2: 60 mg every 12 hours.§[9] | Safety and efficacy of prophylactic doses in patients with obesity (BMI >30 kg/m2) has not been fully determined, and there is no consensus for dose adjustment. Observe carefully for signs and symptoms of VTE.[10] Marginal increase observed in mean anti-factor Xa activity using TBW and 1.5 mg/kg once-daily dosing in healthy persons with obesity (BMI 30 to 48 kg/m2) compared with healthy persons with lower BMI.[10] |
| Dalteparin | Use standard treatment dosing (ie, 200 units/kg once daily based on TBW for the first month, followed by 150 units/kg TBW once daily for subsequent months).¶¥ May consider using 100 units/kg based on TBW every 12 hours for patients weighing ≥90 kg.[11] The labeled indication in the United States for adult patients is extended treatment of cancer-associated VTE.[12] | BMI 30 to 39 kg/m2: Use standard prophylaxis dosing (ie, 5000 units once daily).[2] BMI ≥40 kg/m2: Empirically increase standard prophylaxis dose by 30% (ie, from 5000 units once daily to 6500 units once daily).Δ◊[2] | Cancer-associated VTE treatment: Use TBW-based dosing for patients weighing up to 99 kg. Use a maximum dose of 18,000 units per day for patients weighing ≥99 kg.¶¥[12] |
| Nadroparin (not available in the United States) | Use standard treatment dosing (ie, 171 anti-factor Xa units/kg once daily based on TBW or 86 units/kg every 12 hours based on TBW).¶‡ | BMI 30 to 39 kg/m2: For orthopedic surgery, use weight-based dosing (ie, 38 anti-factor Xa units/kg once daily based on TBW increasing on postoperative day 4 to 57 anti-factor Xa units/kg once daily); for general surgery use standard fixed dosing (ie, 2850 anti-factor Xa units once daily); for medically ill patients use standard fixed dosing (ie, 5700 anti-factor Xa units once daily provided TBW >70 kg).[2] BMI ≥40 kg/m2: For orthopedic surgery, use weight-based dosing (ie, 38 anti-factor Xa units/kg once daily based on TBW increasing on postoperative day 4 to 57 anti-factor Xa units/kg once daily); for general surgery, empirically increase fixed dose by ~30% (ie, increase from 2850 to 3800 anti-factor Xa units once daily); for medically ill patients, empirically increase fixed dose by ~30% (ie, increase from 5700 to 7400 anti-factor Xa units once daily provided TBW >70 kg).Δ◊[2] | Safety and efficacy of LMWHs in high-weight (ie, >120 kg) patients has not been fully determined. Individualized clinical and laboratory monitoring is recommended (Canada product monograph).[13] VTE treatment: Use TBW-based dosing for patients weighing up to 100 kg. Use a maximum dose of 17,100 anti-Xa units per day for patients weighing >100 kg.¶‡[13] |
| Tinzaparin (not available in the United States) | Use standard treatment dosing (ie, 175 anti-factor Xa units/kg once daily based on TBW).¶ | BMI 30 to 39 kg/m2: For orthopedic surgery, use weight-based prophylaxis dosing (ie, 50 or 75 anti-factor Xa units/kg based on TBW once daily); for general surgery and medically ill patients, use standard fixed dosing (ie, 3500 or 4500 anti-factor Xa units once daily depending upon level of VTE risk).[2] BMI ≥40 kg/m2: For orthopedic surgery, use weight-based prophylaxis dosing (ie, 50 or 75 anti-factor Xa units/kg based on TBW once daily); for general surgery and medically ill patients, empirically increase fixed dose by 30% (ie, increase from 3500 to 4500 anti-factor Xa units once daily or from 4500 to 6000 anti-factor Xa units once daily depending on level of VTE risk).Δ◊[2] Moderate to high VTE-risk bariatric surgery, extended postoperative prophylaxis regimen: According to a protocol evaluated at one center: Beginning on postoperative day 1: 75 units/kg based on TBW once daily for 10 days; patients weighing <110 kg received 4500 units once daily; patients weighing ≥160 kg received 14,000 units once daily.Δ§[14] | Safety and efficacy in patients weighing >120 kg has not been fully determined. Individualized clinical and laboratory monitoring is recommended (Canada product monograph).[15] |
All doses shown are for patients with normal kidney function and are for subcutaneous administration. For dose adjustment due to kidney impairment, refer to drug monographs included within UpToDate.
Generally, anti-factor Xa monitoring is not recommended, but it can be considered for patients with BMI ≥40 kg/m2 who are unstable, experience unexpected thromboembolic or bleeding complications, or require prolonged VTE treatment.FDA: Food and Drug Administration; LMWH: low molecular weight heparin; TBW: total body weight, also known as actual body weight; VTE: venous thromboembolism.
* Conversion: 1 mg enoxaparin is approximately equal to 100 international units enoxaparin.
¶ The 2018 American Society of Hematology (ASH) guidelines and other expert reviews suggest against dose reduction or use of a maximum dose for VTE treatment in patients with a high BMI citing consequences of therapeutic failure and lack of correlation between anti-factor Xa concentrations and increased bleeding risk.[2,16]
Δ Rounding of the dose may be necessary depending on product detail. Refer to drug monograph included with UpToDate.
◊ An empiric dose increase of approximately 30% for fixed prophylactic doses of LMWH for VTE prophylaxis for patients with a high BMI is based on clinical experience, expert opinion, and analysis of pharmacodynamic and clinical outcomes data.[2]
§ An optimal approach to thromboprophylaxis in bariatric surgery patients has not been established; there is considerable variability in approach among surgeons and programs. For additional information refer to UpToDate topics on bariatric surgery and institutional protocols.
¥ According to the US FDA approved dalteparin prescribing information, a fixed dose of 18,000 units per day is recommended for patients weighing ≥99 kg who are being treated for cancer-associated VTE.[12] However, guidelines suggest that dalteparin dose should be based on TBW.[2,15] Capped dalteparin dose of 18,000 units per day is not recommended.
‡ According to the Canadian approved nadroparin product monograph, a fixed dose of 17,100 units per day is recommended for patients weighing more than 100 kg.[13] However, guidelines suggest that nadroparin dose should be based on TBW.[2,16] Capped nadroparin dose of 17,100 units per day is not recommended.Do you want to add Medilib to your home screen?
