Home Drug Guide Efavirenz

Drug Guide

Generic Name

Efavirenz

Brand Names Sustiva, Efavirenz 200mg Scored Tablets

Classification

Therapeutic: Antiretroviral, anti-HIV agent

Pharmacological: Non-nucleoside reverse transcriptase inhibitor (NNRTI)

FDA Approved Indications

  • Treatment of HIV-1 infection in combination with other antiretroviral agents

Mechanism of Action

Efavirenz binds directly to reverse transcriptase enzyme, causing inhibition of viral RNA-dependent DNA polymerase, preventing viral replication.

Dosage and Administration

Adult: 600 mg once daily, taken on an empty stomach at bedtime

Pediatric: Not established for children under 3 years; for older children, dose based on weight and age, under medical supervision

Geriatric: No specific dosage adjustment required but caution advised due to potential for increased adverse effects

Renal Impairment: Use with caution; no specific dosage adjustment recommended but monitor closely

Hepatic Impairment: Use with caution; dose adjustment may be necessary, especially in severe hepatic impairment.

Pharmacokinetics

Absorption: Well absorbed orally, peak plasma levels in 3-5 hours

Distribution: Widely distributed; crosses blood-brain barrier

Metabolism: Extensively metabolized in the liver via CYP2B6 and CYP3A4 enzymes

Excretion: Metabolites excreted in urine and feces

Half Life: Approximately 40-55 hours

Contraindications

  • Hypersensitivity to efavirenz or any component of the formulation

Precautions

  • Use with caution in patients with mental health disorders, history of suicidal thoughts, or cardiovascular risk factors; potential for hepatotoxicity; pregnant women should consult healthcare providers due to risk of teratogenicity

Adverse Reactions - Common

  • Central nervous system effects (dizziness, insomnia, vivid dreams) (Common)
  • Rash (Common)
  • Gastrointestinal disturbances (Common)

Adverse Reactions - Serious

  • Psychosis, severe depression, suicidal ideation (Rare)
  • Hepatotoxicity including hepatitis and failure (Rare)

Drug-Drug Interactions

  • Rifampin, St. John’s Wort, other hepatically metabolized drugs

Drug-Food Interactions

  • High-fat meals may increase absorption, so take consistently with or without food as prescribed

Drug-Herb Interactions

  • St. John’s Wort may reduce efavirenz levels

Nursing Implications

Assessment: Monitor hepatic function, mental health status, and emergence of adverse effects

Diagnoses:

  • Risk for neuropsychiatric effects
  • Risk for hepatotoxicity

Implementation: Administer at bedtime to reduce CNS side effects; adherence counseling; regular lab monitoring

Evaluation: Assess for adverse effects, treatment efficacy, and adherence

Patient/Family Teaching

  • Take on an empty stomach at bedtime
  • Do not skip doses; adherence is critical
  • Report new or worsening mental health symptoms, rash, or jaundice immediately
  • Avoid alcohol and concomitant hepatotoxic drugs

Special Considerations

Black Box Warnings:

  • Potential for serious psychiatric symptoms and suicidality; for women of childbearing potential, risk of teratogenicity

Genetic Factors: CYP2B6 slow metabolizers may have higher plasma concentrations, increasing risk of toxicity

Lab Test Interference: Can cause false-positive results in some drug tests

Overdose Management

Signs/Symptoms: Dizziness, rash, vomiting, somnolence, ataxia

Treatment: Supportive care; no specific antidote; consider activated charcoal if ingestion is recent; monitor cardiac if overdose severe

Storage and Handling

Storage: Store below 25°C, away from light and moisture

Stability: Stable under recommended storage conditions

🛡️ 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.