Nurses Compass
Drug Guide
Nelfinavir Mesylate
Classification
Therapeutic: Antiretroviral (HIV protease inhibitor)
Pharmacological: Protease inhibitor
FDA Approved Indications
- Treatment of HIV-1 infection in combination with other antiretroviral agents
Mechanism of Action
Nelfinavir inhibits the HIV-1 protease enzyme, preventing the cleavage of the Gag-Pol polyprotein, resulting in the production of immature, non-infectious viral particles.
Dosage and Administration
Adult: Delivered orally, typically 750 mg twice daily with meals.
Pediatric: Dosed based on weight or age, detailed dosing should be guided by a pediatric HIV specialist.
Geriatric: No specific dosage adjustment; assess renal and hepatic function.
Renal Impairment: Use with caution; no specific dosing adjustments recommended, but limited data available.
Hepatic Impairment: Use with caution; hepatic impairment may increase drug levels.
Pharmacokinetics
Absorption: Well absorbed with food.
Distribution: Widely distributed; protein binding approximately 98%.
Metabolism: Primarily metabolized in the liver via CYP3A4 enzyme.
Excretion: Excreted mainly in feces; minimal renal excretion.
Half Life: Approximately 3–5 hours.
Contraindications
- Hypersensitivity to nelfinavir or any component.
- Concomitant use with certain drugs due to significant drug interactions.
Precautions
- Use with caution in patients with hepatic impairment; monitor liver function.
Adverse Reactions - Common
- Diarrhea (Common)
- Nausea (Common)
- Flattening of the T waves on ECG (rare) (Rare)
Adverse Reactions - Serious
- Hepatotoxicity (Uncommon)
- Drug hypersensitivity reactions (Rare)
- Lipodystrophy, hyperlipidemia (Uncommon)
Drug-Drug Interactions
- Many due to CYP3A4 metabolism; includes statins, sedatives, antihistamines, and others.
Drug-Food Interactions
- High-fat meals increase absorption, but concurrent use with liver-inhibiting drugs may increase adverse effects.
Drug-Herb Interactions
- Potential interactions with herbal supplements affecting CYP3A4 activity.
Nursing Implications
Assessment: Monitor for signs of adverse reactions, adherence, and signs of opportunistic infections.
Diagnoses:
- Impaired skin integrity related to lipodystrophy or rash.
- Risk for infection due to immune suppression.
Implementation: Ensure proper dosing with food, monitor liver function tests, and assess for drug interactions.
Evaluation: Evaluate viral load response, adverse reactions, and adherence.
Patient/Family Teaching
- Take medication with food to enhance absorption.
- Report any signs of liver problems, severe diarrhea, or rash.
- Maintain regular follow-up appointments for blood tests.
Special Considerations
Black Box Warnings:
- No black box warnings for nelfinavir.
Genetic Factors: None specific.
Lab Test Interference: Can cause elevations in liver enzymes; may interfere with certain lab assays.
Overdose Management
Signs/Symptoms: Nausea, vomiting, diarrhea, dizziness, sedation.
Treatment: Supportive care, monitor vital signs, and symptomatic treatment. No specific antidote.
Storage and Handling
Storage: Store at room temperature, away from moisture and light.
Stability: Stable under proper storage conditions.