This page contains brief details about the drug , it's indication, dosage & administaration, mechanism of action, related brands with strength, warnings and common side effects.

Background and Date of Approval

Heparin received its initial FDA approval on June 12, 1939. It was one of the first anticoagulant medications approved by the United States Food and Drug Administration (FDA) for clinical use. 

Mechanism of Action of undefined

Heparin enhances the activity of antithrombin III, a natural anticoagulant protein in the body. By binding to antithrombin III, this medication accelerates its inhibitory effect on clotting factors, particularly thrombin and factor Xa. This inhibition disrupts the blood coagulation cascade, preventing fibrin formation, an essential component of blood clots. As a result, this medication effectively reduces the risk of clot formation and growth, making it a valuable anticoagulant used in various medical conditions.

Uses of undefined

Heparin is used to prevent and treat blood clots in conditions such as deep vein thrombosis (DVT), pulmonary embolism (PE), and during certain medical procedures and surgeries.

undefined Drug administaration and Dosage available

Heparin is administered intravenously (IV) or subcutaneously (under the skin). The specific dosage and administration method depends on the medical condition being treated, the patient's weight, age, and other factors, which a healthcare professional should determine. For IV use, this medication is usually given in a hospital setting under continuous monitoring to adjust the dosage as needed. Subcutaneous injections are often used for prophylactic purposes or in outpatient settings. 

Warnings, Precautions and Side Effects of undefined


Serious bleeding complications can occur, such as gastrointestinal bleeding, intracranial bleeding (bleeding within the skull), or bleeding in other organs. HIT is a rare but potentially severe immune reaction that can occur in some patients treated with heparin. It leads to a significant decrease in platelet count and an increased risk of blood clotting (thrombosis).  This medication use in patients undergoing spinal or epidural anesthesia or puncture can lead to the formation of a hematoma (blood clot) in or around the spine. This can cause pressure on the spinal cord, resulting in long-term or permanent paralysis. Elderly and frail patients may be more susceptible to the side effects of heparin, particularly bleeding complications.


Patients receiving heparin should be closely monitored for signs of bleeding, such as unusual bruising, bleeding from gums or nose, blood in urine or stool, and prolonged bleeding from cuts. If HIT is suspected, this medication should be discontinued immediately, and alternative anticoagulation should be initiated. Special caution is required in patients receiving heparin and regional anesthesia, and the procedure should be performed only if the benefits outweigh the risks. Close monitoring and appropriate dosage adjustments are essential in the elderly population.

Side Effects

Heparin may cause several side effects, including both common and serious reactions. Common side effects include bruising, hematomas (blood collections under the skin), pain at the injection site, and elevated liver enzyme levels. Serious side effects encompass bleeding, which can manifest as unusual bruising, bleeding gums, nosebleeds, blood in urine or stool, and prolonged bleeding from cuts. 

Word Of Advice

Patients should inform their healthcare providers about their medical history, including any bleeding disorders, liver or kidney problems, recent surgeries, and allergies, to determine the appropriate dosage and administration method. Regular monitoring of blood clotting parameters, such as activated partial thromboplastin time (aPTT) or anti-Xa assay, is crucial to maintain the desired anticoagulant effect and prevent bleeding or thrombosis. Patients should follow the prescribed dosage and administration instructions precisely and report any unusual bleeding, bruising, or allergic reactions promptly. It is advisable to avoid activities or medications that may increase the risk of bleeding while on heparin. By adhering to these instructions and maintaining open communication with healthcare providers, patients can minimize risks and maximize the benefits of this therapy.

Frequently Asked Question


  1. Wockhardt UK Ltd, Electronic medicines compendium (EMC), [Revised on June 2018] [ Accessed on 30th July 2023],
  2. Baxter Healthcare Corporation, US Food, and Drug Administration, [Accessed on 30th July 2023],
  3. KD Tripathi, Essentials of Medical Pharmacology, Drugs affecting coagulation, bleeding, and thrombosis, 7th edition, 2013, 617


The drug information on this page is not a substitute for medical advice, it is meant for educational purposes only. For further details, consult your doctor about your medical condition to know if you can receive this treatment.