1. Heparin injectable solution only comes as a generic drug. It doesn’t have a brand-name version.
  2. Heparin comes in two forms. One is an injectable solution, which you inject under your skin. The other is a solution that’s injected intravenously (into one of your veins). Only your doctor can give you the intravenous form.
  3. Heparin injectable solution is a blood thinner that’s used to treat and prevent blood clots.
  • Low platelet levels warning. This drug can decrease your platelet levels. This is known as heparin-induced thrombocytopenia (HIT), which can eventually lead to the formation of blood clots in your veins. These clots can form even several weeks after you stop taking heparin. Your doctor will check you for low platelet levels.
  • Bleeding risk warning. This drug may cause serious bleeding. This happens because this drug reduces your body’s ability to make your blood clot. Heparin may cause you to bruise more easily. It also may take your body longer to stop bleeding. This can cause death in rare cases. Let your doctor know if you have frequent nosebleeds, unusual bleeding from your gums, periods that are heavier than normal, red or brown urine, or dark or tarry stools. Also let your doctor know if you vomit blood, if your vomit looks like coffee grounds, or if you have headaches, dizziness, or weakness.

Heparin is a prescription drug. It comes as a self-injectable solution that you inject under your skin. It also comes as a solution that a healthcare provider injects intravenously (into one of your veins). You can only receive the intravenous form in the hospital.

For the injectable solution, you’ll receive your first injection at a hospital. A healthcare provider will show you how to give yourself the injection. You will give yourself the remaining doses at home.

Heparin injectable solution is only available as a generic drug.

Why it’s used

Heparin is a blood thinner that’s used to treat and prevent blood clots. These can include venous thrombosis, pulmonary embolism, and peripheral arterial embolism.

How it works

Heparin belongs to a class of drugs called anticoagulants. A class of drugs is a group of medications that work in a similar way. These drugs are often used to treat similar conditions.

Heparin works by disrupting the formation of blood clots in your veins. It can prevent blood clots from forming, or stop clots that have already formed from getting larger.

Heparin injectable solution doesn’t cause drowsiness, but it can cause other side effects.

More common side effects

The more common side effects of this drug include:

  • bruising more easily
  • bleeding that takes longer to stop
  • irritation, pain, redness, or sores at the injection site
  • allergic reactions, such as hives, chills, and fever
  • increased liver enzymes on liver function test results

If these effects are mild, they may go away within a few days or a couple of weeks. If they’re more severe or don’t go away, talk to your doctor or pharmacist.

Serious side effects

Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects and their symptoms can include the following:

  • Severe bleeding. Symptoms can include:
    • bruising more easily
    • unexpected bleeding or bleeding that lasts a long time, such as:
      • unusual bleeding from your gums
      • frequent nosebleeds
      • periods that are heavier than normal
    • pink or brown urine
    • dark, tarry stool (may be a sign of bleeding in your stomach)
    • severe bleeding or bleeding that you can’t stop
    • coughing up blood or blood clots
    • vomit that contains blood or looks like coffee grounds
    • headaches
    • weakness
    • dizziness
  • Serious allergic reactions. Symptoms can include:
    • skin tissue death at the injection site
    • chills
    • fever
    • rash and hives
    • itching
    • burning
    • shortness of breath
    • swelling of your face, lips, throat, or tongue
  • Heparin-induced thrombocytopenia. This is low platelet levels caused by heparin use. It can cause new or worsening clots in your blood vessels. These may lead to a stroke or heart attack. Symptoms of new or worsening blood clots can include:
    • reddening and swelling of one leg or arm
    • coughing up blood

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this information includes all possible side effects. This information is not a substitute for medical advice. Always discuss possible side effects with a healthcare provider who knows your medical history.

Heparin injectable solution can interact with other medications, vitamins, or herbs you may be taking. An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well.

To help avoid interactions, your doctor should manage all of your medications carefully. Be sure to tell your doctor about all medications, vitamins, or herbs you’re taking. To find out how this drug might interact with something else you’re taking, talk to your doctor or pharmacist.

Examples of drugs that can cause interactions with heparin are listed below.

Interactions that can increase your risk of side effects

Taking heparin with certain drugs can increase your risk of bleeding and make you bruise more easily. Examples of these drugs include:

  • aspirin
  • nonsteroidal anti-inflammatory drugs such as celecoxib, ibuprofen, and naproxen
  • antiplatelet drugs such as clopidogrel and dipyridamole
  • hydroxychloroquine
  • herbal supplements such as ginkgo biloba, fish oil, and garlic

Interactions that can make heparin less effective

When used with heparin, certain drugs can make heparin less effective. Examples of these drugs include:

  • digoxin
  • tetracycline antibiotics such as doxycycline and minocycline
  • nicotine
  • nitrates, such as isosorbide, mononitrate, and nitroglycerin
  • antihistamines such as diphenhydramine

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs interact differently in each person, we cannot guarantee that this information includes all possible interactions. This information is not a substitute for medical advice. Always speak with your healthcare provider about possible interactions with all prescription drugs, vitamins, herbs and supplements, and over-the-counter drugs that you are taking.

This drug comes with several warnings.

Allergy warning

Heparin can cause a severe allergic reaction. Symptoms can include:

  • skin tissue death at the injection site
  • chills
  • fever
  • rash
  • hives
  • itching
  • burning
  • shortness of breath
  • swelling of your face, lips, throat, or tongue

If you develop these symptoms, call 911 or go to the nearest emergency room.

Don’t take this drug again if you’ve ever had an allergic reaction to it. Heparin is derived from animal tissue. It should be used with caution in people with a history of allergy to this drug or to pig proteins. Taking heparin could be fatal (cause death).

Warnings for people with certain health conditions

For people with pig protein sensitivity: Do not take this drug. This drug is made from pork tissue and can cause a life-threatening allergic reaction in people who are sensitive or allergic to other pig proteins.

For people with uncontrolled high blood pressure: You are at an increased risk of bleeding from this drug. Talk to your doctor before using heparin.

For people with bleeding or clotting problems: If you have abnormal bleeding or a condition that puts you at an increased risk of bleeding, using heparin could increase your risk even more. Use heparin with caution.

For people with a history of stomach ulcers or bleeding: If you have active stomach ulcers, you should not use heparin. It could make your ulcers worse and cause dangerous bleeding. If you have a history of stomach ulcers but don’t have active ulcers, using heparin puts you at an increased risk of bleeding. You should talk to your doctor before using heparin.

For people with kidney disease: If you have severe kidney disease or a history of kidney disease, taking heparin can increase your risk of bleeding. Talk to your doctor before using heparin.

For people with liver disease: If you have severe liver disease or a history of liver disease, taking heparin can increase your risk of bleeding. Talk to your doctor before using heparin.

For people with asthma or sulfite sensitivity: People with asthma are likely to be sensitive to sulfites. Sulfites can cause a life-threatening allergic reaction in some people. Some forms of this drug contain sulfites. Talk to your doctor about using a sulfite-free version of heparin.

Warnings for other groups

For pregnant women: Research in animals has shown negative effects to the fetus when the mother uses heparin. However, there haven’t been enough studies done in humans to be certain how the drug might affect the fetus.

Talk to your doctor if you’re pregnant or plan to become pregnant. This drug should only be used if the potential benefit justifies the potential risk. Ask your doctor if using the preservative-free version of heparin would be better for you than the version that contains benzyl alcohol.

If you become pregnant while taking this drug, call your doctor right away.

For women who are breastfeeding: Heparin is unlikely to pass into breast milk and be absorbed by an infant who is breastfed. Talk to your doctor about the best way to feed your child while you’re taking heparin.

Some forms of heparin contain a preservative called benzyl alcohol. This ingredient can slow down the central nervous system in some infants. It has also caused trouble breathing and changes in the blood chemistry in some infants. These effects can be deadly. If you breastfeed your child, talk to your doctor about preservative-free heparin.

For seniors: If you are older than 60 years, you may be at a higher risk of bleeding. Heparin also increases your risk of bleeding, so your doctor may start you on a reduced dosage.

For children: This medication has not been studied in children. Dosage recommendations are based on clinical experience.

Newborns and infants should receive preservative-free heparin. The preservative benzyl alcohol has been linked to serious side effects and even death in newborns and infants.

All possible dosages and drug forms may not be included here. Your dosage, drug form, and how often you take the drug will depend on:

  • your age
  • the condition being treated
  • how severe your condition is
  • other medical conditions you have
  • how you react to the first dose

Drug forms and strengths

Generic: Heparin

  • Form: injectable solution, preservative-free
  • Strengths: 1,000 units/mL, 10,000 units/mL
  • Form: injectable solution preserved with benzyl alcohol
  • Strengths: 1,000 units/mL, 5,000 units/mL, 10,000 units/mL, 20,000 units/mL

Dosage for deep vein thrombosis and pulmonary embolism

Adult dosage (ages 18–59 years)

  • Typical starting dosage: 333 units/kg of body weight injected under your skin.
  • Typical maintenance dosage: 250 units/kg of body weight injected under your skin every 12 hours. Change the injection site each time to prevent a blood clot from forming at the injection site.

Child dosage (ages 0–17 years)

Your doctor will determine your child’s dosage based on your child’s condition and medical history.

Senior dosage (ages 60 years and older)

You may be at higher risk of bleeding. Your doctor may start you on a reduced dosage.

Dosage for preventing deep vein thrombosis after surgery

Adult dosage (ages 18–59 years)

  • Typical dosage: Your doctor or nurse will give you 5,000 units about 2 hours before your surgery.
  • Typical maintenance dosage: 5,000 units injected under your skin every 8–12 hours. You’ll give yourself this dosage for 7 days or until you can start walking.

Child dosage (ages 0–17 years)

Your doctor will determine your child’s dosage based on your child’s condition and medical history.

Senior dosage (ages 60 years and older)

You may be at higher risk of bleeding. Your doctor may start you on a reduced dosage.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this list includes all possible dosages. This information is not a substitute for medical advice. Always speak with your doctor or pharmacist about dosages that are right for you.

Heparin injectable solution is used for short-term treatment. It comes with serious risks if you don’t take it as prescribed.

If you stop taking the drug suddenly or don’t take it at all: You may develop a blood clot, or an existing blood clot could get worse. These blood clots can be fatal (cause death).

If you miss doses or don’t take the drug on schedule: Your medication may not work as well or may stop working completely. For this drug to work well, a certain amount needs to be in your body at all times.

If you take too much: You could have dangerous levels of the drug in your body, which could lead to serious bleeding. This can be deadly. Symptoms of an overdose of this drug can include:

  • bruising easily
  • unexpected bleeding or bleeding that lasts a long time, such as:
    • unusual bleeding from your gums
    • frequent nosebleeds
    • in women: periods that are heavier than normal
  • pink or brown urine
  • dark, tarry stool (may be a sign of bleeding in the stomach)
  • severe bleeding or bleeding that you can’t stop
  • coughing up blood or blood clots
  • vomit that contains blood or looks like coffee grounds
  • headaches
  • weakness
  • dizziness

If you think you’ve taken too much of this drug, call your doctor or local poison control center. If your symptoms are severe, call 911 or go to the nearest emergency room right away.

What to do if you miss a dose: Take your dose as soon as you remember. If you remember just a few hours before your next scheduled dose, take only one dose. Never try to catch up by taking two doses at once. This could result in dangerous side effects, such as serious bleeding.

How to tell if the drug is working: You should not develop a blood clot, or the clot you currently have should go away.

Keep these considerations in mind if your doctor prescribes heparin for you.

Self-management

  • Your doctor will show you how to give yourself the injection.
  • Use this drug only if the solution is clear and the seal is intact. Do not use this drug if the solution is cloudy, discolored, or has particles in it.

Storage

Store heparin at room temperature between 68°F and 77°F (20°F and 25°C).

Refills

A prescription for this medication is refillable. You should not need a new prescription for this medication to be refilled. Your doctor will write the number of refills authorized on your prescription.

Travel

When traveling with your medication:

  • Always carry your medication with you. When flying, never put it into a checked bag. Keep it in your carry-on bag.
  • Don’t worry about airport x-ray machines. They can’t harm your medication.
  • You may need to show airport staff the pharmacy label for your medication. Always carry the original prescription-labeled container with you.
  • Don’t put this medication in your car’s glove compartment or leave it in the car. Be sure to avoid doing this when the weather is very hot or very cold.
  • You need needles and syringes to take this medication. Check for special rules about traveling with your medication, needles, and syringes.

Clinical monitoring

Your doctor will monitor how well heparin is working for you by doing coagulation or clotting tests. The results of these tests will also help your doctor choose the right dosage of heparin for you.

Your doctor should test you to help make sure you stay safe while you take this drug. These tests check your:

  • Kidney function. If your kidneys are not working well, you may have a higher risk of bleeding. Your doctor will monitor your kidneys to make sure this drug is safe for you to take.
  • Liver function. If your liver is not working well, you may have a higher risk of bleeding. Your doctor will monitor your liver to make sure this drug is safe for you to take.
  • Signs of bleeding. Your doctor may check your platelet and hematocrit levels. They may do a test that checks for blood that may be hidden in your stool. This monitoring helps make sure you don’t bleed too much while you take this drug.

Availability

Not every pharmacy stocks this drug. When filling your prescription, be sure to call ahead to make sure your pharmacy carries it.

Hidden costs

You may need to purchase:

  • sterile alcohol wipes
  • needles and syringes
  • a sharps container (a bin for disposing used needles safely)

There are other drugs available to treat your condition. Some may be better suited for you than others. Talk to your doctor about other drug options that may work for you.

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up-to-date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or other healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.