Viramune (nevirapine) is a non-nucleoside reverse transcriptase inhibitor (NNRTI) indicated for use in combination with other antiretroviral agents for the treatment of HIV-1 infection in adults and pediatric patients. As a cornerstone of many antiretroviral regimens, it works by binding directly to reverse transcriptase, blocking RNA-dependent and DNA-dependent DNA polymerase activities. This action prevents the replication of the virus, thereby reducing viral load and supporting immune reconstitution. Proper patient selection and adherence to monitoring guidelines are essential to maximize therapeutic outcomes and minimize risks.

Features

• Active ingredient: Nevirapine 200 mg
• Formulation: Immediate-release tablets and oral suspension
• Pharmacologic class: Non-nucleoside reverse transcriptase inhibitor (NNRTI)
• Half-life: Approximately 45 hours (single dose), 25–30 hours (multiple dosing)
• Metabolism: Hepatic, primarily via CYP450 isoenzymes (CYP3A4 and CYP2B6)
• Excretion: Primarily renal (81%) and fecal (10%)
• Bioavailability: >90% following oral administration

Benefits

• Potent and selective inhibition of HIV-1 reverse transcriptase, reducing viral replication
• Helps achieve and maintain undetectable viral loads when used in combination therapy
• Supports immune recovery by increasing CD4+ cell counts
• Convenient twice-daily dosing supports regimen adherence
• Available in multiple formulations suitable for adults and children
• Demonstrated efficacy in both treatment-naïve and experienced patients

Common use

Viramune is used as part of combination antiretroviral therapy (cART) for the management of HIV-1 infection. It is typically prescribed for adults, adolescents, and children aged 15 days and older. It may be used in both treatment-naïve and treatment-experienced patients who have not previously received nevirapine. The drug is often included in first-line regimens due to its efficacy, though careful patient screening and initial dosing are critical. It is not active against HIV-2.

Dosage and direction

Adults: The recommended initiation dose is one 200 mg tablet once daily for the first 14 days (lead-in period), followed by one 200 mg tablet twice daily. This gradual introduction helps reduce the risk of rash.
Pediatric patients: Dosage is based on body surface area or body weight. Oral suspension is available for younger patients.
Viramune must be taken consistently, with or without food. Do not exceed recommended doses. Adherence to the lead-in period is mandatory. Treatment should not be reinitiated in patients who discontinue due to severe rash, rash with constitutional symptoms, or hepatic events.

Precautions

• Severe and life-threatening skin reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis, have occurred. Monitor closely during the first 18 weeks.
• Hepatotoxicity, including fatal hepatic events, has been reported. Monitor ALT, AST, and bilirubin at baseline, before dose escalation, and regularly throughout therapy.
• Patients with higher CD4+ counts at initiation (women >250 cells/mm³, men >400 cells/mm³) are at increased risk for hepatic events. Use alternative therapy in these patients unless benefit clearly outweighs risk.
• Immune reconstitution syndrome may occur; monitor for inflammatory responses to opportunistic infections.
• Use with caution in patients with renal impairment; no dose adjustment is generally needed, but monitor for adverse events.

Contraindications

• Hypersensitivity to nevirapine or any component of the formulation
• Moderate to severe hepatic impairment (Child-Pugh Class B or C)
• Use in patients who previously experienced severe rash, hypersensitivity reactions, or clinically significant hepatitis due to nevirapine
• Coadministration with rifampin-based regimens for tuberculosis unless clearly indicated with close monitoring

Possible side effect

Common side effects include rash, nausea, headache, fatigue, and abnormal liver function tests. Serious adverse reactions may include:

• Severe skin reactions (e.g., Stevens-Johnson syndrome)
• Hepatotoxicity, including fulminant hepatitis
• Immune reconstitution inflammatory syndrome (IRIS)
• Hypersensitivity reactions
• Hematologic abnormalities

Most mild to moderate rashes occur within the first 6 weeks of therapy. Discontinue permanently if severe rash or rash with systemic symptoms develops.

Drug interaction

Nevirapine is a moderate inducer of CYP3A4 and may decrease concentrations of drugs metabolized by this pathway. Significant interactions include:

• Reduced concentrations of: ketoconazole, methadone, oral contraceptives, protease inhibitors (e.g., atazanavir, lopinavir)
• Potential increased metabolism of: rifabutin, warfarin, calcium channel blockers
• Use with St. John’s wort is not recommended

Consult full prescribing information before coadministration.

Missed dose

If a dose is missed, take it as soon as remembered. If it is almost time for the next dose, skip the missed dose and resume the regular schedule. Do not double the dose.

Overdose

There is no specific antidote for nevirapine overdose. Symptoms may include edema, erythema nodosum, fatigue, fever, headache, insomnia, nausea, pulmonary infiltrates, rash, vertigo, and weight decrease. Management includes supportive measures and monitoring of vital signs, liver function, and hematologic parameters. Hemodialysis is unlikely to remove significant amounts of nevirapine due to high protein binding.

Storage

Store tablets and suspension at 20–25°C (68–77°F); excursions permitted between 15–30°C (59–86°F). Keep in the original container, tightly closed. Protect from light and moisture. Do not freeze the oral suspension. Keep out of reach of children.

Disclaimer

This information is intended for healthcare professionals. Viramune should be used only under the supervision of a physician experienced in the treatment of HIV infection. Please refer to the full prescribing information for complete details regarding indications, dosing, warnings, and adverse reactions. Individual patient results may vary.

Reviews

Clinical trials and post-marketing experience support the efficacy and generally acceptable tolerability of Viramune in appropriate patient populations. In the INCAS trial, nevirapine in combination with zidovudine and didanosine resulted in undetectable viral loads (<20 copies/mL) in 51% of patients at 52 weeks. Real-world evidence confirms its role in durable viral suppression, though careful patient selection and monitoring remain imperative. Patient satisfaction often relates to its simple dosing and long-term tolerability when managed correctly.