Efavirenz / Emtricitabine / Tenofovir Disoproxil Dosage

Medically reviewed by Drugs.com. Last updated on Apr 4, 2025.

Applies to the following strengths: 600 mg-200 mg-300 mg

Usual Adult Dose for HIV Infection

1 tablet orally once a day

Use: As a complete regimen or in combination with other antiretroviral agents for the treatment of HIV-1 infection

Usual Adult Dose for Nonoccupational Exposure

US CDC Recommendations: 1 tablet orally once a day
Duration of therapy: 28 days

Comments:

Only with expert consultation, an alternative regimen for HIV nonoccupational postexposure prophylaxis (nPEP)
Efavirenz is contraindicated as nPEP in pregnant women; it should be avoided in nPEP regimens during the first trimester and should not be used for women of childbearing potential who might become pregnant during antiretroviral prophylaxis.
Prophylaxis should be started as soon as possible, within 72 hours of exposure.
Current guidelines should be consulted for additional information.

Usual Adult Dose for Occupational Exposure

US Public Health Service working group recommendations: 1 tablet orally once a day
Duration of therapy: 28 days, if tolerated

Comments:

Only with expert consultation, an alternative regimen for use as HIV postexposure prophylaxis
Prophylaxis should be started as soon as possible, preferably within hours after exposure.
The optimal duration of prophylaxis is unknown and may differ based on institution protocol.
Current guidelines should be consulted for additional information.

Usual Pediatric Dose for HIV Infection

At least 40 kg: 1 tablet orally once a day

Use: As a complete regimen or in combination with other antiretroviral agents for the treatment of HIV-1 infection

Renal Dose Adjustments

Moderate or severe renal dysfunction (estimated CrCl less than 50 mL/min): Not recommended.

Liver Dose Adjustments

Mild liver dysfunction (Child-Pugh A): No adjustment recommended; caution recommended.
Moderate to severe liver dysfunction (Child-Pugh B or C): Not recommended.

Dose Adjustments

Concomitant rifampin:

Patients weighing at least 50 kg: After administration of this drug (1 tablet orally once a day), an additional 200 mg/day of efavirenz is recommended.

Precautions

US BOXED WARNING:

POSTTREATMENT ACUTE EXACERBATION OF HEPATITIS B: Severe acute exacerbations of HBV reported in patients coinfected with HIV-1 and HBV after stopping products containing emtricitabine and/or tenofovir disoproxil fumarate. Hepatic function of HIV-1/HBV-coinfected patients should be closely monitored with clinical and laboratory follow-up for at least several months after stopping this drug. If appropriate, initiation of antihepatitis B therapy may be necessary.

CONTRAINDICATIONS:

Previously demonstrated clinically significant hypersensitivity (e.g., Stevens-Johnson syndrome, erythema multiforme, toxic skin eruptions) to efavirenz
Coadministration with voriconazole or elbasvir-grazoprevir

Safety and efficacy have not been established in pediatric patients weighing less than 40 kg; this drug is not recommended for use in these patients.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

Test patients for HBV infection before or when starting this drug.
In all patients, assess serum creatinine, estimated CrCl, urine glucose, and urine protein before starting and during therapy as clinically appropriate; in patients with chronic kidney disease, also assess serum phosphorus.
Monitor hepatic function before and during therapy.
Perform pregnancy testing before starting this drug in adolescents and adults of childbearing potential.
Administer on an empty stomach.
Dosing at bedtime may improve tolerability of nervous system symptoms.

Storage requirements:

Store in the original bottle; keep bottle tightly closed.
Store at 25C (77F); excursions permitted to 15C to 30C (59F to 86F).

General:

Each 3-drug fixed-dose combination tablet contains efavirenz 600 mg, emtricitabine 200 mg, and tenofovir disoproxil fumarate 300 mg.

Monitoring:

General: Pregnancy testing in patients of childbearing potential (before starting therapy)
Hepatic: Liver enzymes/hepatic function (before and during therapy); for chronic HBV in all patients (before therapy); hepatic function of HIV-1/HBV-coinfected patients with clinical and laboratory follow-up (for at least several months after stopping therapy)
Infections/Infestations: For chronic HBV infection in all patients (before or when starting therapy)
Metabolic: Serum phosphorus in patients with chronic kidney disease (before starting and as clinically appropriate during therapy)
Musculoskeletal: Bone mineral density in patients with history of pathologic bone fracture or other risk factors for osteoporosis or bone loss
Renal: Serum creatinine, estimated CrCl, urine glucose, and urine protein in all patients (before starting and as clinically appropriate during therapy)

Patient advice:

Read the US FDA-approved patient labeling (Patient Information).
If you also have HBV, do not stop this drug without consulting healthcare provider.
Contact physician without delay if rash occurs.
Watch for early signs of liver inflammation or failure (e.g., fatigue, weakness, lack of appetite, nausea and vomiting) as well as later signs (e.g., jaundice, confusion, abdominal swelling, discolored feces); consult healthcare professional at once if such symptoms occur.
Seek immediate medical evaluation if severe psychiatric side effects occur.
Avoid potentially hazardous tasks (e.g., driving, operating machinery) if CNS symptoms (e.g., dizziness, impaired concentration, drowsiness) occur.
Avoid taking this drug with concurrent/recent use of nephrotoxic agents.
If of childbearing potential, avoid pregnancy and inform healthcare provider if you become pregnant or plan to become pregnant while using this drug; always use a reliable form of barrier contraception with other methods of contraception (including oral or other hormonal contraception) during therapy and for 12 weeks after stopping this drug.
Notify healthcare provider at once of any symptoms of infection.
Take this drug on a regular dosing schedule to avoid missing doses.