Efavirenz is an inhibitor of the reverse transcriptase enzyme that allows the reduction of the HIV particles in the blood.


What is Efavirenz?


Efavirenz is used in combination with other medications to control the infection caused by HIV. While not curing it, it helps to counteract its evolution in acquired immunodeficiency syndrome (AIDS), the appearance of diseases associated with the presence of the virus, such as severe infections or cancers, and the risk of transmitting the virus through unprotected sex.

The efavirenz can also be administered with other drugs to help reduce the risk of infection in people accidentally exposed to the virus.


How should Efavirenz be taken?


The efavirenz is commercially available for oral use in the form of capsules or tablets. Generally, it should be taken once a day on an empty stomach, with water. It is recommended to take it before going to bed because it can help reduce the impact of possible side effects.


Side effects associated with Efavirenz


The possible side effects associated with efavirenz may include:


  • Mood swings
  • Dizziness
  • Confusion
  • Diarrhea
  • Difficulty falling asleep and staying asleep
  • Difficulty concentrating
  • General ache or pain
  • Stomach discomfort
  • Indigestion
  • Headache
  • Nervousness
  • Forgetfulness
  • Strange dreams
  • Drowsiness
  • Vomiting


It is important to contact a doctor immediately if the active ingredient triggers any of the following symptoms:


  • Convulsions
  • Pain in the upper right abdomen
  • Unexpected bleeding or bruising
  • Skin exfoliation
  • Jaundice
  • Loss of appetite
  • Itching
  • Rash
  • Flu-like symptoms
  • Extreme fatigue or loss of energy
  • Fainting
  • Blisters on the skin


Contraindications and warnings associated with the use of Efavirenz


Efavirenz should not be taken with astemizole, cisapride, ergot derivatives, midazolam, triazolam, and voriconazole as well as in cases of pregnancy and/or breastfeeding.


Moreover, prior to beginning treatment with this medication you should tell your doctor if:


  • You have any allergies to the active substance or other drugs
  • You are taking other medications, herbal remedies and other supplements, especially ibuprofen, anticoagulants, antifungals, calcium channel blockers, chlorpheniramine, statins, cimetidine, clarithromycin, danazol, dexamethasone, the erythromycin, iron supplements, isoniazid, medications for anxiety, depression or pain, those against HIV or AIDS, indinavir, lopinavir, ritonavir and saquinavir, anticonvulsants, methotrexate, methadone, metronidazole, niacin, NSAIDs, oral antidiabetic drugs, proton pump inhibitors, quinidine, quinine, rifabutin, rifampin, sedatives, sertraline, sildenafil, sleeping pills, sulfamethoxazole, tamoxifen, torsemide, tranquilizers, troleandomycin, zafirlukast, the St. John's herbs and kava
  • You suffer from problems with the abuse of alcohol, drugs or medications
  • You are suffering (or have suffered) from seizures, depression or other psychiatric disorders as well as heart, kidney or pancreatic disease
  • You are suffering from high cholesterol levels


It is also important to remember that efavirenz can interfere with your ability to drive or operate dangerous machinery, which can trigger changes in mood and personality. Furthermore, prior to undergoing any surgical procedure, it is necessary to inform surgeons and dentists that you are taking this medication.