NEVIRAPINE

NEVIRAPINE
(ne-vir'a-peen)
Viramune
Classifications: antiretroviral agent; nonnucleoside reverse transcriptase inhibitor (nnrti);
Therapeutic:antiretroviral; nnrti
Prototype: Efavirenz
Pregnancy Category: C

Availability

200 mg tablets; 10 mg/mL suspension

Action

Nonnucleoside reverse transcriptase inhibitor (NNRI) of HIV-1. Binds directly to reverse transcriptase and blocks RNA- and DNA-dependent polymerase activities, thus preventing replication of the virus.

Therapeutic Effect

Prevents replication of the HIV-1 virus. Does not inhibit HIV-2 reverse transcriptase and DNA polymerases such as alpha, beta, gamma, and delta polymerases. Resistant strains appear rapidly.

Uses

In combination with nucleoside analogs for treatment of HIV.

Contraindications

Hypersensitivity to nevirapine; hormonal contraceptives; pregnancy (category C), neonates; lactation.

Cautious Use

Liver or renal disease, hemodialysis; hepatitis B or C; CNS disorders.

Route & Dosage

HIV
Adult: PO 200 mg once daily for first 14 d, then increase to 200 mg b.i.d.
Child: PO 120 mg/m² q.d. x 14 d, then increase q12h, if tolerated, to 120–200 mg/m² q12h (max: 200 mg/dose)

Administration

Oral

Reinitiate with 200 mg/d for 14 d, then increase to b.i.d. dosing, when dosing is interrupted for >7 d.
Store at 15°–30° C (59°–86° F) in a tightly closed container.

Adverse Effects (≥1%)

Body as a Whole: Fever, paresthesia, myalgia. CNS: Headache. GI: Nausea, diarrhea, abdominal pain, hepatitis, increased liver function tests, hepatotoxicity (including fulminant and cholestatic hepatitis, hepatic necrosis, and hepatic failure, especially with long-term use). Hematologic: Anemia, neutropenia. Skin: Rash, Stevens-Johnson syndrome.

Interactions

Drug: May decrease plasma concentrations of protease inhibitors, oral contraceptives; may decrease methadone levels inducing opiate withdrawal. Herbal: St. John's wort , garlic may decrease antiretroviral activity.

Pharmacokinetics

Absorption: Rapidly from GI tract. Peak: 4h. Distribution: 60% protein bound, crosses placenta, distributed into breast milk. Metabolism: In liver (CYP3A). Elimination: Primarily in urine. Half-Life: 25–40 h.

Nursing Implications

Assessment & Drug Effects

Lab tests: Obtain baseline and periodic liver and kidney function tests, routine blood chemistry, and CBC.
Monitor weight, temperature, respiratory status with chest x-ray throughout therapy.
Monitor carefully, especially during first 6 wk of therapy, for severe rash (with or without fever, blistering, oral lesions, conjunctivitis, swelling, joint aches, or general malaise).
Withhold drug and notify physician if rash develops or liver function tests are abnormal.

Patient & Family Education

Learn about common adverse effects.
Withhold drug and notify physician if severe rash appears.
Do not drive or engage in potentially hazardous activities until response to drug is known. There is a high potential for drowsiness and fatigue.
Use or add barrier contraceptive if using hormonal contraceptive.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug

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