Dalteparin

What is dalteparin?

Dalteparin is an anticoagulant and blood-thinner medication used off label (extra label) to treat and prevent thromboembolism (blood clots) in dogs, cats, and horses. Dalteparin is classified as a low-molecular-weight heparin (LMWH), also known as fragmented heparin.

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 dalteparin?

• Dalteparin is given by injection under the skin only (subcutaneously, or SQ). 
• Patients are often hospitalized during treatment because the injections may need to be given frequently.
• If you are giving the injections at home, be sure you understand the proper dosage, location, and method for giving the shots.
• Do not shake the vial as doing so may break up the fragile drug molecule and destroy the drug’s effectiveness.
• Your veterinarian will provide a very small needle for you to use, because the medication is very strong and given in very small amounts. Most pet owners administer it with insulin syringes.
• Use a new needle and syringe for each injection; do not reuse needles and syringes.
• Place used needles and syringes in a sharps disposal container that your veterinarian provides. Once it is about ¾ full, dispose of the containers according to your community guidelines.
• Do not use any medication that has changed color or has specks in it.
• Be careful not to accidentally stick yourself; do not disconnect the needle from the syringe.

This medication should take effect within 1 to 2 hours; however, effects may not be noted outwardly, so laboratory tests will be needed to evaluate this medication’s effectiveness.

What if I miss giving my pet the medication?

If you miss a dose of dalteparin, give it as soon as you remember, and then continue with the regular dosing schedule. However, if it is almost time for the next dose, skip the missed dose and resume the regular dosing schedule. Do not give the pet two doses at once.

Are there any potential side effects from dalteparin?

Dalteparin may cause the following side effects:

• Pain or bruising at the injection site

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

• Bleeding, due to a decrease in clotting times (rare)
• Signs of an allergic reaction (facial swelling, hives, itching, difficulty breathing)
• Fever

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. 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 can be longer in pets with liver or kidney disease.

Are there any risk factors for this medication?

DO NOT USE dalteparin in:

• Pets with active major bleeding
• Pets with a history of heparin-induced thrombocytopenia
• Pets with a known hypersensitivity to dalteparin, heparin, or pork products

USE WITH EXTREME CAUTION in:

• Pets receiving epidural anesthesia
• Pets with an increased risk for bleeding

USE WITH CAUTION in:

• Pets that have received warfarin or other anticoagulants due to increased risk of bleeding
• Pets with kidney dysfunction
• Pets with the MDR1/ABCB1 genetic mutation

Some dog breeds are more sensitive than others to medications (e.g., collies, sheepdogs, and collie- or sheepdog-cross breeds). This sensitivity is typically due to a genetic mutation (MDR1/ABCB1) that makes them less able to tolerate high doses of certain medications. Use dalteparin cautiously in these cases.

Are there any drug interactions I should be aware of?

Certain medications may interact with dalteparin, so 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. Several medications should be used with caution when given with dalteparin, including:

• Aspirin
• Clopidogrel
• Glycosaminoglycans
• Nonsteroidal anti-inflammatory drugs (NSAIDs) such as meloxicam, carprofen
• Warfarin or other anticoagulants (due to increased risk of bleeding)

Is any monitoring needed with this medication?

• A complete blood cell count should be performed before treatment starts and periodically during treatment.
• Urine testing is recommended during treatment.
• Fecal occult blood testing is recommended in horses.
• Anti-factor Xa may be used to monitor anticoagulant effects.
• At home, monitor for any side effects such as those noted above. If any side effects occur, discontinue use of the medication and contact your veterinarian.
• Your veterinarian will let you know when they want to reassess your pet to ensure the medication is working and not causing side effects.

How do I store dalteparin?

• This medication can be stored at room temperature; however, if your veterinarian or pharmacist has drawn the medicine into syringes, they may suggest it be stored in the refrigerator.
• Use multiple-dose vials within two weeks of initial penetration.
• Store in an airtight container.
• Protect from light and heat.
• 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.