NELFINAVIR MESYLATE
| NELFINAVIR MESYLATE (nel-fin'a-vir) Viracept Classifications: antiretroviral agent; protease inhibitor; Therapeutic:antiretroviral; protease inhibitor Prototype: Saquinavir Pregnancy Category: B |
Availability
250 mg, 625 mg tablets; 50 mg/g powder
Action
Inhibits HIV-1 protease, which is responsible for the production of HIV-1 viral particles in an infected individual. Inhibition of the viral protease prevents the cleavage of the viral polypeptide, resulting in the production of an immature, noninfectious virus.
Therapeutic Effect
Effectiveness is indicated by decreased viral load.
Uses
Treatment of HIV infection in combination with a nucleoside analog.
Contraindications
Hypersensitivity to nelfinavir; concurrent administration with amiodarone, quinidine, rifampin, triazolam, or midazolam; lactation. Safety and effectiveness in children <2 y are not established.
Cautious Use
Liver function impairment, hemophilia; pregnancy (category B).
Route & Dosage
| HIV Infection Adult: PO 750 mg t.i.d. or 1250 mg (2 x 625 mg) b.i.d. with food Child (2–13 y): PO 20–30 mg/kg t.i.d. with food (max: 750 mg/dose) |
Administration
Oral- Give with a meal or light snack.
- Oral powder may be mixed with a small amount of water, milk, soy milk, or dietary supplements; liquid should be consumed immediately. Do not mix oral powder in original container nor with acid food or juice (e.g., orange or apple juice, or applesauce).
- Store at 15°–30° C (59°–86° F).
Adverse Effects (≥1%)
Body as a Whole: Allergic reactions, back pain, fever, malaise, pain, asthenia, myalgia, arthralgia. CNS: Headache, anxiety, depression, dizziness, insomnia, seizures. GI: Abdominal pain, diarrhea, nausea, flatulence, anorexia, dyspepsia, GI bleeding, hepatitis, vomiting, pancreatitis, increased liver function tests. Hematologic: Anemia, leukopenia, thrombocytopenia. Respiratory: Dyspnea, pharyngitis, rhinitis. Skin: Rash, pruritus, sweating, urticaria.Interactions
Drug: Other protease inhibitors, ketoconazole may increase nelfinavir levels; rifabutin, rifampin may decrease nelfinavir levels; nelfinavir will decrease oral contraceptive levels; may increase levels of atorvastatin, simvastatin; increase risk of ergotamine toxicity with dihydroergotamine, ergotamine. Herbal: St. John's wort, garlic may decrease antiretroviral activity.Pharmacokinetics
Absorption: Food increases the amount of drug absorbed. Distribution: >98% protein bound. Metabolism: In the liver (CYP3A). Elimination: Primarily in feces. Half-Life: 3.5–5 h.Nursing Implications
Assessment & Drug Effects
- Monitor hemophiliacs (type A or B) closely for spontaneous bleeding.
- Monitor carefully patients with hepatic impairment for toxic drug effects.
Patient & Family Education
- Drug must be taken exactly as prescribed. Do not alter dose or discontinue drug without consulting physician.
- Use a barrier contraceptive even if using hormonal contraceptives.
- Be aware that diarrhea is a common adverse effect that can usually be controlled by OTC medications.
Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; 
Canadian drug name; 
Prototype drug