Summary Safety Review - Low-Molecular-Weight Heparins - Assessing the potential risk of bleeding in or around the spinal cord (Spinal/Epidural Hematoma)

Review decision

A Summary Safety Review complements other safety related information to help Canadians make informed decisions about their use of health products. Each summary outlines what was assessed in Health Canada’s review, what was found and what action was taken by Health Canada, if any.


Issued: 2017-02-08

Product

Low-molecular-weight heparins

Potential Safety Issue

Spinal/epidural hematoma

Key Messages

  • Low-molecular-weight heparins (LMWH) are prescription drugs which are authorized for sale in Canada to treat or prevent blood clots.
  • Health Canada reviewed information related to the known, rare risk of bleeding in or around the spinal cord (spinal/epidural hematoma) in patients receiving LMWH to prevent blood clots while undergoing spinal/epidural anaesthesia or spinal puncture. The review was initiated because of an update by the United States Food and Drug Administration (FDA) to the safety information for LMWH related to this risk.
  • Health Canada's review concluded that the risk of bleeding may increase if the spinal procedure is carried out soon after injection of LWMH. Health Canada requested that the manufacturers of LMWH update the Canadian safety information to include information on the recommended length of time between LMWH injection and spinal/epidural anaesthesia or spinal puncture. This length of time can vary, but should be determined by the prescriber in accordance with recommendations in the Canadian safety information.

Overview

Health Canada reviewed information related to the known, rare risk of bleeding in or around the spinal cord (spinal/epidural hematoma) in patients receiving LMWH to prevent blood clots while undergoing spinal/epidural anaesthesia or spinal puncture. The review was initiated because of an update to the United States product safety information for LMWH related to this risk.

Use in Canada

  • LMWH are prescription drugs which are authorized for sale in Canada to treat or prevent blood clots.
  • LMWH have been marketed in Canada since 1993 and are currently sold under the brand names Fragmin, Fraxiparine/Fraxiparine Forte, Innohep and Lovenox/Lovenox HP. LMWH products are available for intravenous and/or subcutaneous injection.

Safety Review Findings

  • At the time of the review, Health Canada had received 2 Canadian casesa of bleeding in or around the spinal cord in patients receiving LMWH and undergoing spinal/epidural anaesthesia or spinal puncture. In these 2 reports, there was not enough information to determine what may have played a role in the bleeding that occurred.
  • This safety review looked at 153 international reports of bleeding in or around the spinal cord in patients receiving LMWH while undergoing spinal/epidural anaesthesia or spinal puncture. In these 153 reports, it was found that a short length of time between LWMH use and the spinal procedure may have increased the risk of bleeding.

Conclusions and actions

  • Health Canada's review concluded that the risk of bleeding may increase if the spinal procedure is carried out soon after injection of LWMH.
  • Health Canada requested that the manufacturers of LMWH update the Canadian safety information to include information on the recommended length of time between LMWH injection and spinal/epidural anaesthesia or spinal puncture. This length of time can vary, but should be determined by the prescriber in accordance with recommendations in the Canadian safety information.
  • Health Canada will continue to monitor safety information for LMWH, as it does for all health products on the Canadian market, to identify and assess potential harms. Health Canada will take appropriate and timely action, if and when any new health risks are identified.

Additional information

The analysis that contributed to this safety review included scientific and medical literature, international adverse reaction reports, and what is known about the use of these drugs both in Canada and internationally.

For additional information, contact the Marketed Health Products Directorate.

Footnotes

  1. Canadian reports can be accessed through the Canada Vigilance Online Database.