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Fragmin Side Effects

Generic Name: dalteparin

Note: This document contains side effect information about dalteparin. Some of the dosage forms listed on this page may not apply to the brand name Fragmin.

In Summary

Common side effects of Fragmin include: pain at injection site. Other side effects include: hematoma at injection site and increased serum alanine aminotransferase. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to dalteparin: subcutaneous injectable, subcutaneous solution

Along with its needed effects, dalteparin (the active ingredient contained in Fragmin) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking dalteparin:

More common
  • Deep, dark purple bruise, pain, or swelling at the injection site
Less common
  • Bleeding of the gums
  • coughing up blood
  • difficulty with breathing or swallowing
  • dizziness
  • headache
  • increased menstrual flow or vaginal bleeding
  • nosebleeds
  • paralysis
  • prolonged bleeding from cuts
  • red or black, tarry stools
  • red or dark brown urine
  • unexplained pain, swelling, or discomfort, especially in the chest, abdomen or stomach, joints, or muscles
  • unusual bruising
  • vomiting of blood or material that looks like coffee grounds
  • weakness
  • Back pain
  • bleeding from mucous membranes
  • bluish or black discoloration, flushing, or redness of the skin
  • burning, pricking, tickling, or tingling sensation
  • coughing
  • feeling faint
  • fever
  • leg weakness
  • numbness
  • problems with bowel or bladder function
  • skin rash (which may consist of pinpoint, purple-red spots), hives, or itching
  • sloughing of the skin at the injection site
  • swelling of the eyelids, face, or lips
  • tightness in the chest

For Healthcare Professionals

Applies to dalteparin: subcutaneous solution


The most common side effects were any bleeding, postoperative transfusion, transaminase increases, and injection site pain.[Ref]


Very common (10% or more): Any bleeding (up to 18.5%)
Common (1% to 10%): Major bleeding reactions
Postmarketing reports: Prosthetic cardiac valve thrombosis[Ref]

A bleeding reaction was considered major if accompanied by a decrease in hemoglobin of 2 g/dL or greater in connection with clinical symptoms, a transfusion was required, bleeding led to interruption of treatment or death, bleeding caused a significant clinical event, bleeding resulted in reoperation, or retroperitoneal or intracranial bleeding occurred.[Ref]


Very common (10% or more): Postoperative transfusion (up to 15.9%)
Common (1% to 10%): Wound hematoma, reoperation due to bleeding[Ref]


Very common (10% or more): Grades 2 through 4 increases in AST and ALT (up to 14%)
Common (1% to 10%): Asymptomatic increases in transaminase levels (serum glutamic oxaloacetic transaminase/AST and Serum glutamic pyruvic transaminase/ALT) greater than 3 times the upper limit of normal, grades 3 and 4 increases in AST and ALT[Ref]

Nervous system

Postmarketing reports: Epidural/spinal hematoma, intracranial bleed[Ref]


Very common (10% or more): Injection site pain (up to 12%)
Common (1% to 10%): Injection site hematoma[Ref]


Common (1% to 10%): Reversible non-immunologically-mediated thrombocytopenia (type I)
Rare (less than 0.1%): Immunologically-mediated heparin-induced thrombocytopenia (type II, with or without associated thrombotic complications)[Ref]


Common (1% to 10%): Hematuria[Ref]


Uncommon (0.1% to 1%): Allergic reaction
Rare (less than 0.1%): Fever
Frequency not reported: Anaphylactoid reaction[Ref]


Uncommon (0.1% to 1%): Rash, urticaria, pruritus
Rare (less than 0.1%): Bullous eruptions, skin necrosis, alopecia[Ref]


Uncommon (0.1% to 1%): Hypersensitivity[Ref]


Uncommon (0.1% to 1%): Hyperkalemia[Ref]


Uncommon (0.1% to 1%): Osteoporosis[Ref]


Postmarketing reports: Hypoaldosteronism[Ref]


Frequency not reported: Gastrointestinal bleeding
Postmarketing reports: Retroperitoneal bleed[Ref]


Frequency not reported: Serum creatinine increased[Ref]


1. Cerner Multum, Inc. "Australian Product Information." O 0

2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

3. "Product Information. Fragmin (dalteparin)." Pharmacia and Upjohn, Kalamazoo, MI.

Some side effects of Fragmin may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.