Home Drug Guide Penciclovir

Drug Guide

Generic Name

Penciclovir

Brand Names Denavir

Classification

Therapeutic: Antiviral

Pharmacological: Nucleoside analog

FDA Approved Indications

  • Herpes labialis (cold sores)

Mechanism of Action

Penciclovir inhibits viral DNA synthesis by acting as a substrate for viral DNA polymerase, leading to chain termination.

Dosage and Administration

Adult: Apply a thin layer to the affected area every 2 hours while awake for 4 days.

Pediatric: Safety and efficacy not established in pediatric patients.

Geriatric: No specific dosage adjustments; monitor for reactions.

Renal Impairment: No specific adjustments recommended; use with caution.

Hepatic Impairment: No data available.

Pharmacokinetics

Absorption: Minimal systemic absorption when applied topically.

Distribution: Limited due to minimal systemic absorption.

Metabolism: Not extensively metabolized.

Excretion: Primarily excreted unchanged in urine.

Half Life: Approximately 2 hours.

Contraindications

  • Hypersensitivity to penciclovir or any component of the formulation.

Precautions

  • Use with caution in patients with immunosuppression or extensive herpes outbreaks. Avoid contact with eyes. Explore potential for resistance.

Adverse Reactions - Common

  • Application site reactions such as redness, itching, or burning. (Common)

Adverse Reactions - Serious

  • Allergic reactions, including rash, swelling, or difficulty breathing. (Rare)

Drug-Drug Interactions

  • None well documented

Drug-Food Interactions

  • None

Drug-Herb Interactions

  • Limited data available

Nursing Implications

Assessment: Assess lesion location, size, and severity before and during treatment.

Diagnoses:

  • Ineffective tissue perfusion related to skin lesion.
  • Risk for infection.

Implementation: Instruct patient to apply medication as prescribed, wash hands before and after application, and avoid touching or squeezing lesions.

Evaluation: Monitor for resolution of lesions and adverse reactions.

Patient/Family Teaching

  • Apply medication as directed, typically 4 times daily for 4 days.
  • Use separate applicator or finger cot to minimize spread.
  • Wash hands before and after application.
  • Avoid touching or picking at lesions.

Special Considerations

Black Box Warnings:

  • None currently.

Genetic Factors: No known genetic factors affecting use.

Lab Test Interference: None noted.

Overdose Management

Signs/Symptoms: Local irritation or systemic symptoms are unlikely due to minimal absorption.

Treatment: Supportive care; no specific antidote.

Storage and Handling

Storage: Store at room temperature away from moisture and heat.

Stability: Stable until expiration date on packaging.

🛡️ 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.