Generic name:
Efavirenz/lamivudine/tenofovir - oral
Pronunciation
(EF-a-VIR-enz/la-MIV-ue-deen/ten-OF-oh-vir)
Brand name(s)
Symfi , Symfi Lo
Generic name:
Efavirenz/lamivudine/tenofovir - oral
Pronunciation
(EF-a-VIR-enz/la-MIV-ue-deen/ten-OF-oh-vir)
Brand name(s)
Symfi , Symfi Lo
If you have hepatitis B infection as well as HIV, your hepatitis symptoms may get worse or become very serious if you stop taking this medication. Talk with your doctor before stopping this medication. Your doctor will check your liver function tests for several months after you stop. Tell your doctor right away if you develop symptoms of worsening liver problems.
This combination product is used by itself to help control HIV infection. It helps to decrease the amount of HIV in your body so your immune system can work better. This lowers your chance of getting HIV complications (such as new infections, cancer) and improves your quality of life. This product is a combination of 3 different drugs: efavirenz, lamivudine, and tenofovir. Efavirenz belongs to a class of drugs known as non-nucleoside reverse transcriptase inhibitors (NNRTIs). Lamivudine is called a nucleoside reverse transcriptase inhibitor and tenofovir is called a nucleotide reverse transcriptase inhibitor. Lamivudine and tenofovir are often called NRTIs.
Efavirenz/lamivudine/tenofovir is not a cure for HIV infection. To decrease your risk of spreading HIV disease to others, continue to take all HIV medications exactly as prescribed by your doctor. Use an effective barrier method (latex or polyurethane condoms/dental dams) during sexual activity as directed by your doctor. Do not share personal items (such as needles/syringes, toothbrushes, and razors) that may have contacted blood or other body fluids. Consult your doctor or pharmacist for more details.
Read the Patient Information Leaflet if available from your pharmacist before you start taking efavirenz/lamivudine/tenofovir and each time you get a refill. If you have any questions, ask your doctor or pharmacist.
Take this medication by mouth as directed by your doctor, usually once daily at bedtime on an empty stomach. Taking this medication at bedtime may help decrease some side effects.
It is very important to keep taking this medication exactly as prescribed by your doctor. Do not skip any doses.
For the best effect, take this medication at evenly spaced times. To help you remember, take this medication at the same time every day.
Do not take more or less of this drug than prescribed or stop taking it even for a short time unless directed to do so by your doctor. Doing so may cause the amount of virus to increase, make the infection more difficult to treat (resistant), or worsen side effects.
Dizziness, trouble sleeping, drowsiness, unusual dreams, and trouble concentrating may commonly occur. These side effects may begin 1 or 2 days after starting this medication, but usually get better within 2 to 4 weeks. Taking this medication at bedtime may help.
Tiredness, headache, and diarrhea may also occur.
If any of these effects last or get worse, tell your doctor or pharmacist promptly.
Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
As your immune system gets stronger, it can begin to fight off infections you already had, possibly causing disease symptoms to come back. You could also have symptoms if your immune system becomes overactive. This reaction may happen at any time (soon after starting HIV treatment or many months later). Get medical help right away if you have any serious symptoms, including:
Tell your doctor right away if you have any serious side effects, including:
Changes in body fat may occur while you are taking this medication (such as increased fat in the upper back and stomach areas, decreased fat in the arms and legs). The cause and long-term effects of these changes are unknown. Discuss the risks and benefits of treatment with your doctor, as well as the possible use of exercise to reduce this side effect.
Tenofovir may increase the risk of bone loss. Discuss the risks and benefits of treatment with your doctor, as well as the possible use of calcium and vitamin D to reduce this side effect. If you are at risk for bone loss, your doctor may monitor your bone mineral density. Tell your doctor right away if any of the following serious side effects occur:
Get medical help right away if you have any very serious side effects, including:
Efavirenz/lamivudine/tenofovir can commonly cause a rash that is usually not serious. However, you may not be able to tell it apart from a rare rash that could be a sign of a severe reaction. Tell your doctor right away if you develop any rash.
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Before taking efavirenz/lamivudine/tenofovir, tell your doctor or pharmacist if you are allergic to any of the ingredients; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of:
Efavirenz/lamivudine/tenofovir may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away.
The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using efavirenz/lamivudine/tenofovir, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions:
Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics "water pills") or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using efavirenz/lamivudine/tenofovir safely.
This drug may make you dizzy or drowsy or cause trouble concentrating. Alcohol or marijuana (cannabis) can worsen these effects. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Avoid alcoholic beverages because they may also worsen the side effects of this medication (such as liver problems, pancreatitis, mental/mood symptoms). Talk to your doctor if you are using marijuana (cannabis).
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Older adults may be more sensitive to the side effects of this drug, especially QT prolongation (see above).
During pregnancy, this medication should be used only when clearly needed. Treatment can lower the risk of passing HIV infection to your baby, and efavirenz/lamivudine/tenofovir may be part of that treatment. Discuss the risks and benefits with your doctor.
This medication passes into breast milk. Because breast milk may transmit HIV, consult your doctor before breastfeeding.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Some products that may interact with this drug are:
Do not take this medication with other products that treat HIV infection. Do not take this medication with other products that contain efavirenz, lamivudine, or tenofovir.
Other medications can affect the removal of efavirenz/lamivudine/tenofovir from your body, which may affect how this product works. Examples include St. John's wort, some drugs used to treat seizures (such as carbamazepine), among others.
Efavirenz/lamivudine/tenofovir can speed up the removal of other medications from your body, which may affect how they work. Examples of affected drugs include atazanavir, atovaquone/proguanil, azole antifungals (such as voriconazole), bedaquiline, cobicistat, elbasvir/grazoprevir, elvitegravir, macrolide antibiotics (such as clarithromycin), sofosbuvir/velpatasvir, among others.
This medication may decrease the effectiveness of hormonal birth control such as pills, patch, or ring. This could cause pregnancy. Discuss with your doctor or pharmacist if you should use reliable backup birth control methods while using this medication. Also tell your doctor if you have any new spotting or breakthrough bleeding, because these may be signs that your birth control is not working well.
Tell your doctor or pharmacist if you are taking other products that cause drowsiness including alcohol, marijuana (cannabis), antihistamines (such as cetirizine, diphenhydramine), drugs for sleep or anxiety (such as diazepam, zolpidem), muscle relaxants, and opioid pain relievers (such as codeine).
Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely.
This medication may interfere with certain lab tests (including urine cannabinoid tests), possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug.
If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.
Do not share this medication with others.
Lab and/or medical tests (such as kidney/liver tests, urine glucose/protein, viral load, T-cell counts, cholesterol and triglyceride levels, blood mineral levels, bone density tests) should be done before you start taking this medication and while you are taking it. Keep all medical and lab appointments.
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.
Store in the original container at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
Information last revised May 2024.
Copyright(c) 2024 First Databank, Inc.
Selected from NATIONAL DRUG DATA FILE (NDDF) data included with permission and copyrighted by First Databank, Inc., 2019. This copyrighted material has been downloaded from a licensed data provider.
The above information is intended to supplement, not substitute for, the expertise and judgment of your health care professional. You should consult your health care professional before taking any drug, changing your diet, or commencing or discontinuing any course of treatment.