FDA Safety Changes: Heparin Sodium Injection, Photofrin, Noroxin

-Medscape

11/28/2008- The US Food and Drug Administration (FDA) has approved safety labeling revisions to warn of the risk for medication errors and heparin-induced thrombocytopenia in patients receiving heparin sodium injection, an increased duration of photosensitivity in patients with renal or hepatic impairment receiving porfimer sodium injection, and the risk for rare but fatal reactions in patients receiving norfloxacin and other quinolone antibiotics.

Heparin Sodium Injection Linked to Fatal Medication Errors, Risk for HIT/HITT

On September 23, the FDA approved safety labeling revisions for parabens-preserved and preservative-free formulations of heparin sodium injection (Abraxis Pharmaceutical Products, LLC) to warn of the risk for medication errors and delayed-onset heparin-induced thrombocytopenia (HIT).

Heparin sodium injection should not be used as a "catheter lock flush" product, the FDA warned, noting that the product is supplied in various strengths that include a highly concentrated 10,000-units/mL solution. Fatal hemorrhages have occurred in infants and neonates because of medication errors in which 1-mL vials of heparin sodium injection were confused with 1-mL "catheter lock flush" vials. All vials should be carefully examined before use to avoid this error.

The FDA also advised of the risk for delayed-onset HIT, a serious antibody-mediated reaction that results from irreversible platelet aggregation and can lead to the development of venous and arterial thrombosis, a condition known as heparin-induced thrombocytopenia and thrombosis (HITT).

HITT can initially present as thrombotic events, including deep vein thrombosis, pulmonary embolism, cerebral vein thrombosis, limb ischemia, stroke, myocardial infarction, mesenteric thrombosis, renal arterial thrombosis, skin necrosis, gangrene of the extremities that can lead to amputation, and possibly death.

The incidence of thrombocytopenia in patients receiving heparin ranges from 0% to 30%. Platelet counts should therefore be obtained at baseline and monitored periodically during treatment. Thrombocytopenia of any degree should be monitored closely; heparin should be discontinued and alternative anticoagulant therapy considered if platelet counts decrease below 100,000/mm3 or if recurrent thrombosis develops.

Because HIT and HITT can occur up to several weeks after heparin is discontinued, they should be considered in the diagnosis of patients presenting with thrombocytopenia or thrombosis after termination of therapy.

Heparin sodium injection is indicated for the prophylaxis and treatment of venous thrombosis, pulmonary embolism, and peripheral arterial embolism; treatment of atrial fibrillation with embolization; diagnosis and treatment of acute and chronic consumptive coagulopathies; and for the prevention of clotting in arterial and cardiac surgery.

It also is indicated for use as an anticoagulant in blood transfusions, extracorporeal circulation, dialysis procedures, and blood samples for laboratory purposes. A low-dose regimen can be used to prevent postoperative deep vein thrombosis and pulmonary embolism in patients undergoing major abdominothoracic surgery and those at risk for the development of thromboembolic disease from other causes.

Porfimer Sodium (Photofrin)-Related Photosensitivity Extended in Certain Patients

On September 8, the FDA approved safety labeling revisions for porfimer sodium injection (Photofrin; Axcan Pharma US, Inc) to warn of the risks associated with its use in patients with hepatic and renal impairment.

All patients receiving treatment with porfimer sodium will be photosensitive and must observe precautions to avoid exposing their skin and eyes to direct sunlight or bright indoor light (eg, dental lamps, operating room lamps, and unshaded light bulbs) for at least 30 days.

Hepatic and renal impairment are expected to prolong the elimination of porfimer sodium, leading to increased rates of toxicity. Because photosensitivity is linked to the presence of residual drug, patients with severe renal impairment or mild to severe hepatic impairment should be advised that precautionary measures against photosensitivity may be required for periods exceeding 90 days.

The FDA notes that conventional ultraviolet sunscreen will only protect against photosensitivity related to ultraviolet light and is of no value in protecting against reactions to visible light.

Porfimer sodium is a photoactivated drug indicated in the treatment of esophageal cancer, endobronchial cancer, and high-grade dysplasia of Barrett's esophagus.

Norfloxacin (Noroxin) and Other Quinolones Linked to Rare but Fatal Events

On September 23, the FDA approved safety labeling revisions for norfloxacin tablets (Noroxin; Merck & Co, Inc) to advise of adverse events associated with this medication and other quinolones.

Serious, and sometimes fatal, events have been reported rarely in patients receiving quinolone therapy, generally occurring after administration of multiple doses. Some of these events were because of hypersensitivity; for others, the cause remains unclear.

Clinical manifestations may include 1 or more of the following: fever, rash, or severe dermatologic reactions (eg, toxic epidermal necrolysis, Stevens-Johnson syndrome); vasculitis, arthralgia, myalgia, and serum sickness; allergic pneumonitis; interstitial nephritis, acute renal insufficiency or failure; hepatitis, jaundice, acute hepatic necrosis or hepatic failure; and anemia, including hemolytic and aplastic forms; thrombocytopenia, including thrombotic thrombocytopenic purpura; leukopenia; agranulocytosis; pancytopenia; and/or other hematologic abnormalities.

The FDA advises that norfloxacin be discontinued and supportive measures instituted at the first appearance of a skin rash, jaundice, or any other sign of hypersensitivity.

Norfloxacin is a fluoroquinolone antibacterial agent indicated for the treatment of adults with urinary tract infections caused by susceptible strains of designated microorganisms, uncomplicated urethral and cervical gonorrhea due to Neisseria gonorrhoeae, and prostatitis due to Escherichia coli.

If you or a loved one have experienced Heparin Sodium Injection side effects you may be entitled to compensation. Contact the Heparin attorneys of Ennis & Ennis today for a free confidential case evaluation. Our on staff nurse and lawyers are standing by to answer any questions you may have regarding Heparin side effects, a possible Heparin class action lawsuit, or any other type of Heparin Sodium Injection litigation.