Enoxaparin (Low Molecular Weight Heparin)

What is enoxaparin?

Enoxaparin, also known as low molecular weight heparin (LMWH), is an anticoagulant (blood thinner) used to prevent or treat blood clots in cats, dogs, and horses. It may be used before surgery to prevent blood clots from forming.

It is used off label (extra label) in veterinary medicine. Many drugs are commonly prescribed for off-label use in veterinary medicine. “Off label” means the drug is being used in a way that has not been reviewed or approved by the U.S. Food and Drug Administration (FDA) or Health Canada. In these instances, follow your veterinarian’s directions and cautions carefully, as they may be significantly different from those on the label.

How do I give my pet enoxaparin?

• Enoxaparin comes in an injectable form.
• Injections are given subcutaneously (under the skin).
• Measure the amount of medication to be given very carefully. Enoxaparin is a strong drug and doses are small and precise.
• Use a new needle and syringe each time you give the medication.
• Follow your veterinarian’s directions on how and where to give the injection.
• Do not shake the vial.
• Dispose of sharps in a designated sharps disposal container.
• Give this medication to your pet for the entire time prescribed by your veterinarian, even if it appears that your pet is feeling better.

This medication should take effect within 1 to 2 hours, although effects will not be noticed outwardly.

What if I miss giving my pet the medication?

If you miss a dose, give it as soon as you remember, and then wait the recommended time for the next dose, as prescribed by your veterinarian. Contact your veterinarian for further directions if you are unsure about dosing or timing – this medication must be given carefully. Do not give the pet two doses at once or change the dose.

Are there any potential side effects?

Enoxaparin may cause the following side effects:

• Itchiness, pain, and/or redness at the injection site

Serious adverse reactions may occur. If any of the following signs develop, stop giving enoxaparin and contact your veterinarian immediately:

• Bleeding, bruising
• Fever
• An allergic reaction such as irregular breathing, rash, fever, puffiness and swelling around the face

Drug sensitivities can develop over time with repeated exposure. Your pet may have no reaction after the first few doses, but may develop a sensitivity later. It is important to watch for signs of an allergic reaction over the entire course of treatment and notify your veterinarian if you have any concerns.

Other side effects may occur. If you notice anything unusual, contact your veterinarian immediately. This short-acting medication should stop working within 24 hours, although effects may last longer in pets with kidney or liver disease.

Are there any risk factors for this medication?

DO NOT USE enoxaparin in:

• Pets that are allergic to any component of the medication (including pork products)
• Pets that are allergic to similar medications (e.g., heparin)

USE WITH CAUTION in:

• Pets with a history of low platelets or other bleeding disorders 
• Pets with kidney disease

Are there any drug interactions I should be aware of?

Certain medications should be USED WITH CAUTION when given with enoxaparin, including:

• Antiplatelet medications (e.g., clopidogrel)
• Nonsteroidal anti-inflammatory drugs (e.g., carprofen, meloxicam)
• Other anticoagulants (e.g., warfarin)
• SSRI antidepressants (e.g., fluoxetine)
• Thrombolytic agents

Be sure to tell your veterinarian about any medications (including vitamins, supplements, or herbal therapies) that your pet is taking before starting any new treatment.

Is any monitoring needed with this medication?

• Your veterinarian may assess a complete blood count (CBC) before starting this medication.
• Your veterinarian may schedule follow-up visits for monitoring. In this case, follow your veterinarian’s directions.
• At home, monitor for any abnormal changes. If these occur, discontinue the medication and contact your veterinarian. 

How do I store enoxaparin?

• Store at room temperature of 77°F (25°C), with excursions permitted between 59°F and 86°F (15°C and 30°C).
• Follow manufacturer’s directions on expiration and discard times.
• Keep medication out of reach of children and pets.

What should I do in case of emergency?

If you suspect an overdose or an adverse reaction to the medication, call your veterinary office immediately. If they are not available, follow their directions in contacting an emergency facility. Be prepared to provide information about the product and your pet's weight and symptoms. Adverse effects should be reported to the FDA or Health Canada.