Home Drug Guide Phenprocoumon

Drug Guide

Generic Name

Phenprocoumon

Brand Names Liquamar

Classification

Therapeutic: Anticoagulant

Pharmacological: Vitamin K antagonist

FDA Approved Indications

  • Prevention and treatment of venous thrombosis, pulmonary embolism, and prevention of thromboembolic complications in atrial fibrillation and prosthetic heart valves

Mechanism of Action

Phenprocoumon inhibits vitamin K epoxide reductase, leading to a decrease in synthesis of vitamin K-dependent clotting factors II, VII, IX, and X, thus exerting an anticoagulant effect.

Dosage and Administration

Adult: Typically 2-8 mg once daily, adjusted based on INR

Pediatric: Not generally recommended; dose individualized if used in rare cases

Geriatric: Start cautiously, with close INR monitoring due to increased bleeding risk

Renal Impairment: Use with caution; no specific dosage adjustments, but monitoring is essential

Hepatic Impairment: Use with caution; dosage adjustments may be necessary, monitoring liver function

Pharmacokinetics

Absorption: Well absorbed orally

Distribution: Widely distributed in body tissues, crosses placenta, appears in breast milk

Metabolism: Hepatic, primarily via CYP450 enzymes

Excretion: Metabolites excreted in urine and bile

Half Life: approximately 5-7 days, enabling once-daily dosing

Contraindications

  • Active bleeding
  • Severe liver disease
  • Known hypersensitivity

Precautions

  • Monitor INR regularly, especially during initiation and dose adjustments
  • Use with caution in patients with recent surgery, trauma, or high bleeding risk

Adverse Reactions - Common

  • Bleeding (Common)

Adverse Reactions - Serious

  • Hemorrhage (Serious, requires urgent intervention)
  • Hepatotoxicity (Rare)
  • Allergic reactions (Rare)

Drug-Drug Interactions

  • Other anticoagulants, antiplatelet agents, NSAIDs, certain antibiotics (e.g., macrolides, rifampin), antifungals

Drug-Food Interactions

  • Foods high in vitamin K (green leafy vegetables), which can decrease efficacy

Drug-Herb Interactions

  • St. John's Wort, ginseng, garlic supplements, which may increase bleeding risk

Nursing Implications

Assessment: Regular INR monitoring, assessment for signs of bleeding or clotting—extremity swelling, chest pain, neurological changes.

Diagnoses:

  • Risk for bleeding
  • Ineffective tissue perfusion related to bleeding risk

Implementation: Administer at same time daily, educate patient to maintain consistent vitamin K intake, monitor INR frequently.

Evaluation: Maintain INR within therapeutic range, observe for bleeding or thrombosis, adjust dose accordingly.

Patient/Family Teaching

  • Take medication at the same time daily.
  • Report any unusual bleeding or bruising promptly.
  • Maintain a consistent diet with regard to vitamin K intake.
  • Inform healthcare providers of all medications and supplements.

Special Considerations

Black Box Warnings:

  • Bleeding risk; monitor INR closely

Genetic Factors: Polymorphisms in VKORC1 and CYP2C9 genes can affect dosing

Lab Test Interference: None significant; INR is a reliable measure for monitoring therapy

Overdose Management

Signs/Symptoms: Excessive bleeding, hematuria, hematemesis, melena, petechiae

Treatment: Discontinue drug, administer vitamin K (phytonadione), provide supportive measures including fresh frozen plasma or prothrombin complex concentrates in severe cases.

Storage and Handling

Storage: Store at room temperature, away from moisture and light

Stability: Stable for 2-3 years if stored properly.

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.