Phytomenadione (Injection)

Generic Details

Generic Name

Phytomenadione Injection

Other Names

  • Vitamin K1 Injection

Drug Class

  • Vitamin

Chemical Formula

C31H46O2

Molecular Weight

450.698 g/mol

Mechanism of Action

  • Phytomenadione is a cofactor for the enzyme gamma-glutamyl carboxylase which catalyzes the conversion of glutamate residues in inactive hepatic precursors to gamma-carboxyglutamate. This post-translational modification permits the calcium-dependent binding of these proteins to phospholipid membranes via gammacarboxyglutamate-containing domains.

Indications

  • Treatment and prevention of hypoprothrombinemia (deficiency of clotting factors) due to vitamin K deficiency or interference with vitamin K activity.

Common Dosage Forms

  • Injection

Typical Dosage

  • Adult dose: 1 to 5 mg injected intravenously or intramuscularly, depending on the severity of the deficiency.

Pediatric Dosage

  • Dosing should be determined by a healthcare provider based on the child's weight and condition.

Geriatric Dosage

  • No specific dosage adjustments are necessary.

Side Effects

  • Pain at the injection site, redness, or swelling may occur. Rarely, allergic reactions may occur such as rash, itching, or difficulty breathing.

Contraindications

  • Hypersensitivity to phytomenadione or any components of the formulation.

Pregnancy Category

  • Category C - Animal reproduction studies have shown an adverse effect on the fetus, and there are no adequate and well-controlled studies in humans.

Lactation Safety

  • It is not known whether phytomenadione passes into breast milk. Consult a healthcare provider before using during breastfeeding.

Drug Interactions

  • Anticoagulant drugs like warfarin may interact with phytomenadione, leading to an increased risk of bleeding.

Overdose Symptoms

  • Excessive doses of phytomenadione may cause hypervitaminosis K, resulting in jaundice, hemolytic anemia, and hyperbilirubinemia in newborns.

Antidote for Overdose

  • There is no specific antidote; treatment is supportive and based on symptoms.

Storage Conditions

  • Store at controlled room temperature between 20°C to 25°C (68°F to 77°F), protect from light.

Pharmacokinetics

  • Absorption: Phytomenadione is rapidly and completely absorbed after intramuscular or subcutaneous administration.
  • Distribution: It is distributed mainly in the liver following administration.
  • Metabolism: Phytomenadione is metabolized in the liver via the hepatic cytochrome P450 system.
  • Excretion: Metabolites are excreted mainly in bile and feces.

Precautions

  • Use with caution in individuals with liver disease or on anticoagulant therapy.

Warnings

  • Intravenous administration should be slow and done under medical supervision to avoid adverse effects like anaphylaxis.