How does this medication work? What will it do for me?
This is a combination product that contains three medications in one tablet: efavirenz, emtricitabine, and tenofovir. These medications belong to the class of medications called antiretrovirals. They are used to treat human immunodeficiency virus (HIV) infection.
Emtricitabine and tenofovir are HIV nucleoside analog reverse transcriptase inhibitors (NRTI) and efavirenz is an HIV non-nucleoside analog reverse transcriptase inhibitor (NNRTI). These medications work by interfering with enzymes that are needed for HIV to multiply, and by lowering the amount of HIV in the blood. They may also help the immune system by increasing the number of CD4 (T) cells in the body.
This medication does not cure HIV infection or acquired immune deficiency syndrome (AIDS), and it does not reduce the risk of passing HIV to others through sexual contact or blood contamination.
This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.
Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.
Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.
What form(s) does this medication come in?
Each pink, oval-shaped, biconvex, film-coated tablet debossed with "K14" on one side and plain on the other side, contains 600 mg of efavirenz, 200 mg of emtricitabine, and 300 mg of tenofovir disoproxil fumarate (which is equivalent to 245 mg of Tenofovir Disoproxil). Nonmedicinal ingredients: croscarmellose sodium, low-substituted hydroxypropyl cellulose, microcrystalline cellulose, hydroxypropyl cellulose, sodium lauryl sulfate, hypromellose, magnesium stearate, and Opadry II Pink 85F94172; Coating: Opadry II Pink 85F94172 (iron oxide black, iron oxide red, polyethylene glycol, polyvinyl alcohol, talc, and titanium dioxide).
How should I use this medication?
The usual dose of this combination medication is 1 tablet taken by mouth, once daily. It should be taken on an empty stomach.
Taking this medication at bedtime may help some of the side effects be less bothersome.
Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.
It is important to use this medication exactly as prescribed by your doctor. If you do not, the amount of HIV virus in your blood may increase and the virus may develop resistance to this medication.
If you miss a dose of this medication, take it as soon as your remember that day. Do not take more than 1 dose in a day. Do not take a double dose to make up for a missed one. If you are not sure what to do if you miss a dose, contact your doctor or pharmacist.
Store this medication at room temperature, in its original container, and keep it out of the reach of children.
Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.
Who should NOT take this medication?
Do not take this medication if you:
- are allergic to efavirenz, emtricitabine, tenofovir, or any ingredients of the medication
- are taking any of the following medications:
- ergot derivatives (e.g., ergotamine, dihydroergotamine)
- St. John's wort
What side effects are possible with this medication?
Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.
The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.
The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.
Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.
- abnormal or unusual dreams
- difficulty concentrating
- muscle or bone pain or weakness
- skin discolouration
- stomach or abdominal pain
- trouble sleeping
Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- abnormal thoughts, hallucination, or delusions
- catatonia (unable to move or talk for a period of time)
- immune system changes (e.g., high fever, joint or muscle pain, redness, rash, swelling, fatigue)
- skin rash
- symptoms of depression (e.g., decreased concentration, difficulty or excessive sleeping, increased or loss of appetite, loss of interest in activities)
- symptoms of liver problems (e.g., yellowing of the skin or whites of the eyes, dark urine, light or pale stools, loss of appetite, nausea and lower abdominal pain)
- symptoms of kidney problems (e.g., increased or decreased urination, swelling of the feet or legs, feeling restless and tired)
- symptoms of pancreatitis (e.g., upper left abdominal pain, back pain, nausea, fever, chills, rapid heartbeat, swollen abdomen)
Stop taking the medication and seek immediate medical attention if any of the following occur:
- signs of a severe skin reaction (e.g., blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort)
- symptoms of a severe allergic reaction (e.g., hives; difficulty breathing; swelling of the face, tongue, mouth, or throat)
- symptoms of lactic acidosis (e.g., unusual weakness or tiredness, unusual muscle pain, stomach pain with nausea and vomiting, feeling cold especially in arms and legs, dizziness or lightheadedness, and fast or irregular heartbeat)
- thoughts of suicide
Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.
Are there any other precautions or warnings for this medication?
Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Bone: This medication may reduce bone mineral density, which increases the risk of fractures. If you experience bone pain or a bone fracture while taking this medication, contact your doctor. Your doctor may do tests to monitor the effects of this medication on your bones. If you have bone problems, talk to your doctor about whether you should take calcium and vitamin D supplements.
Cholesterol: Antiretroviral medications can increase levels of lipids (fat) in the blood. If you have high blood cholesterol levels, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Diabetes: This medication may cause an increase in blood sugar levels (may cause a loss of blood glucose control) and glucose tolerance may change. People with diabetes may find it necessary to monitor their blood sugar more frequently while using this medication.
Drowsiness/reduced alertness: This medication may interfere with activities requiring mental alertness. People taking this medication should not drive or operate machinery until they know how this medication affects them.
Heart rhythm: Efavirenz can cause changes to the normal rhythm of the heart, including an irregular heartbeat called QT prolongation. QT prolongation is a serious life-threatening condition that can cause fainting, seizures, and sudden death. If you are at risk for heart rhythm problems (e.g., people with heart failure, angina, low potassium or magnesium levels), discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Hepatitis B: The safety of using this medication for people who are infected with hepatitis B has not been established. If this medication is used to treat HIV for people who have hepatitis B, the hepatitis B may worsen when this medication is stopped. If you also have hepatitis B and stop using this medication, your doctor will monitor your liver function closely for several months.
Hepatitis C: Tenofovir interacts with many of the medications used to treat hepatitis C. If you are taking other antiretroviral medications, discuss with your doctor how this medication may affect your other medications, how it may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Immune reconstitution syndrome: This medication may cause immune reconstitution syndrome, where signs and symptoms of inflammation from previous infections appear. These symptoms occur soon after starting anti-HIV medication and can vary. They are thought to occur as a result of the immune system improving and being able to fight infections that have been present without symptoms (such as pneumonia, herpes, or tuberculosis). Report any new symptoms to your doctor immediately.
Kidney function: The kidneys remove emtricitabine and tenofovir from the body. Kidney disease or decreased kidney function may cause these medications to build up in the body, causing side effects. This medication may also cause kidney problems, including kidney failure. If you have reduced kidney function or kidney disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Your doctor may monitor your kidney function with blood tests while you are taking this medication. Additional tests may be needed if you have a history of kidney problems or if you need to take another medication that can cause kidney problems.
Lactic acidosis/enlarged liver: This medication can cause a rare but serious condition called lactic acidosis, together with an enlarged liver. This tends to occur more often for women, especially those who are overweight. If you have any symptoms of this condition such as nausea, vomiting, stomach pain, weakness, tiredness, feeling cold, dizziness, lightheadedness, or sudden slow or irregular heartbeat, stop taking this medication and contact your doctor immediately.
Liver: This medication can cause liver problems. If you have reduced liver function or liver disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. Report any signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools) to your doctor immediately.
Mental health/behaviour: Some people who take this medication experience severe depression, strange thoughts, or angry behaviour. Some people have experienced thoughts of suicide and have committed suicide while taking this medication. These symptoms seem to occur more often for people with a history of mental conditions. Talk to your doctor immediately if you experience any of these symptoms.
If you have mental health concerns, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Other medications for HIV: There are several combination medications available to treat HIV infection, and many of these have combinations that include one or more of the ingredients in this medication. They may also include ingredients that work the same way as the ingredients in this medication. Taking two combination medications is dangerous and can cause fatal drug interactions. With your doctor or pharmacist, review the ingredients of any medication that may be prescribed and compare it to the medications you are currently taking.
Pancreatitis: This medication may cause inflammation of the pancreas (pancreatitis). If you have a history of pancreatitis or are at risk for developing pancreatitis, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. If you develop signs of pancreatitis (e.g., upper left abdominal pain, back pain, nausea, fever, chills, rapid heartbeat, swollen abdomen), contact your doctor.
Seizures: Although it is uncommon, seizures have been reported by people taking this medication; usually by people who already had seizure disorders. If you have a history of seizures, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. If you experience a seizure while taking this medication, get immediate medical attention.
Skin rashes: This medication can cause mild-to-moderate skin rash. However, sometimes a skin reaction can be severe. If you develop a skin rash with fever, fatigue, blisters, muscle aches, or sores in and around the mouth, stop taking this medication and contact your doctor immediately.
Pregnancy: Efavirenz may harm the developing baby if it is taken by the mother while she is pregnant. Women should avoid becoming pregnant while taking this medication and for 12 weeks after stopping it. Your doctor should test you for pregnancy before starting this medication. You should also use at least two methods of birth control while taking this medication, including one barrier method (e.g., condoms). If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: It is not known if this medication passes into breast milk. However, breast-feeding is not recommended for HIV-positive women since the virus can be passed to the baby through breast-milk.
Children: The safety and effectiveness of using this medication have not been established for children.
What other drugs could interact with this medication?
There may be an interaction between efavirenz - emtricitabine - tenofovir and any of the following:
- alpha-blockers (e.g., alfuzosin, doxazosin, silodosin, tamsulosin)
- aminoglycoside antibiotics (e.g., amikacin, gentamicin, tobramycin)
- antiarrhythmics (e.g., amiodarone, disopyramide, flecainide, procainamide, propafenone, quinidine)
- anti-cancer medications (e.g., cabazitaxel, docetaxel; doxorubicin; etoposide, ifosfamide, irinotecan, vincristine)
- antihistamines (e.g., cetirizine, doxylamine, diphenhydramine, hydroxyzine, loratadine)
- antipsychotics (e.g., chlorpromazine, clozapine, haloperidol, olanzapine, quetiapine, risperidone)
- antiviral medications (e.g., acyclovir, cidofovir, ganciclovir, valacyclovir, valganciclovir)
- "azole" antifungals (e.g., itraconazole, ketoconazole, posaconazole, voriconazole)
- barbiturates (e.g., butalbital, pentobarbital, phenobarbital)
- benzodiazepines (e.g., chlordiazepoxide, clobazam, clonazepam, diazepam, lorazepam)
- birth control pills
- calcium channel blockers (e.g., diltiazem, felodipine, nifedipine, verapamil)
- chloral hydrate
- ergot derivatives (e.g., ergotamine, dihydroergotamine)
- estrogens (e.g., conjugated estrogen, estradiol, ethinyl estradiol)
- general anesthetics (medications used to put people to sleep before surgery)
- ginkgo biloba
- "gliptin" diabetes medications (e.g., linagliptin, saxagliptin, sitagliptin)
- hepatitis C antivirals (e.g., elbasvir, glecaprevir and pibrentasvir, grazoprevir, ledipasvir, sofosbuvir)
- HIV integrase inhibitors (e.g., dolutegravir, elvitegravir, raltegravir)
- other HIV non-nucleoside reverse transcriptase inhibitors (NNRTIs; e.g., etravirine, nevirapine)
- other HIV nucleoside reverse transcriptase inhibitors (NRTIs; e.g., abacavir, didanosine, lamivudine, zidovudine)
- HIV protease inhibitors (e.g., atazanavir, indinavir, ritonavir, saquinavir)
- lumacaftor and ivacaftor
- macrolide antibiotics (e.g., azithromycin, clarithromycin, erythromycin)
- muscle relaxants (e.g., baclofen, cyclobenzaprine, methocarbamol, orphenadrine)
- narcotic pain relievers (e.g., codeine, fentanyl, morphine, oxycodone)
- non-steroidal anti-inflammatory medications (NSAIDs; e.g., diclofenac, ibuprofen, naproxen)
- progestins (e.g., dienogest, levonorgestrel, medroxyprogesterone, norethindrone)
- protein kinase inhibitors (e.g., bosutinib, dasatinib, erlotinib, imatinib, nilotinib)
- proton pump inhibitors (e.g., lansoprazole, omeprazole)
- quinolone antibiotics (e.g., ciprofloxacin, norfloxacin, ofloxacin)
- St. John's wort
- seizure medications (e.g., carbamazepine, clobazam, levetiracetam, phenobarbital, phenytoin, primidone, topiramate, valproic acid, zonisamide)
- serotonin antagonists (anti-emetic medications; e.g., granisetron, ondansetron)
- sodium oxybate
- "statin" anticholesterol medications (e.g., atorvastatin, pravastatin, simvastatin)
- sulfonylureas (e.g., chlorpropamide, glipizide, glyburide)
- tetracycline antibiotics (e.g., doxycycline, minocycline, tetracycline)
- thiazolidinediones (e.g., pioglitazone, rosiglitazone)
- tricyclic antidepressants (e.g., amitriptyline, clomipramine, desipramine, trimipramine)
If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:
- stop taking one of the medications,
- change one of the medications to another,
- change how you are taking one or both of the medications, or
- leave everything as is.
An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.
Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.
All material copyright MediResource Inc. 1996 – 2023. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: www.medbroadcast.com/drug/getdrug/Auro-Efavirenz-Emtricitabine-Tenofovir