What Is Efavirenz?
Efavirenz is a non-nucleoside reverse transcriptase inhibitor used to treat, prevent, and spread HIV.
Efavirenz forms a part of the highly active antiretroviral therapy or HAART for treating HIV type 1 infection.
In people whose HIV has not been previously treated, a combination of efavirenz and lamivudine with zidovudine or tenofovir can be effective.
Efavirenz may be prescribed to all adults and children above three months of age who are heavier than eight pounds.
Efavirenz should always be given in combination with other HIV medications.
It is never prescribed as a sole drug.
What Is Efavirenz Used For?
Efavirenz is an antiviral medication that prevents the multiplication of HIV in the body and its transmission to other individuals.
This drug can prevent the development of AIDS (Acquired ImmunoDeficiency Syndrome) but does not cure HIV.
How Does Efavirenz Work?
Efavirenz belongs to the class of non-nucleoside reverse transcriptase inhibitors.
HIV uses a reverse transcriptase enzyme to copy its genetic code to make a copy of itself that can enter human cells.
Non-nucleoside reverse transcriptase inhibitors prevent or inhibit HIV’s reverse transcriptase enzyme activity.
As a result, efavirenz reduces the amount of HIV in the blood.
Efavirenz does not cure HIV but decreases the risk of developing AIDS and other HIV-related infections and cancer.
Taking efavirenz with other HIV medications may help reduce the spread and transmission of the virus.
Side Effects Of Efavirenz
Efavirenz is used safely in people who have HIV.
However, it may cause side effects in some individuals.
- An itchy rash, usually a week after taking the drug
- Abdominal pain
- Mental health issues like depression, anxiety
- Lack of sleep
- Poor concentration and coordination
- Raised cholesterol levels, and changes in body fat
If you experience any of the symptoms mentioned above after taking efavirenz, speak to your doctor immediately.
Other serious side effects of efavirenz that requires immediate medical attention include:
- Nervous system symptoms like unusual dreams, drowsiness
- Immune system changes like immune reconstitution inflammatory syndrome or IRIS and increased frequency of infections
- Psychiatric symptoms like paranoia, strange dreams
- Trouble speaking or swallowing
- Swelling in your neck or throat
Does Efavirenz Cause Weight Gain?
While efavirenz does not cause weight gain, it does cause an increase in blood cholesterol and triglycerides in the blood.
A study published in 2018 stated that adults living who switched from a daily dose of efavirenz to an INSTi-based regime gained weight more than those who continued with the drug.
Does Efavirenz Cause Hepatotoxicity?
Efavirenz is used as the first line of treatment for HIV.
Though the exact mechanism is not clear, efavirenz is associated with hepatotoxicity (injury to the liver or impairment of liver function).
This hepatotoxicity results from a full-body hypersensitivity reaction to the drug, characterized by skin rash and fever.
Does Efavirenz Cause Depression?
Nervous system and psychiatric side effects of efavirenz are common.
A study conducted on rats in 2005 reported that efavirenz might induce depression-like behavior in rats.
The same study also found that the rats were more susceptible to stress when on efavirenz.
Has Efavirenz Been Discontinued?
Though efavirenz is still being used with other antiretroviral medications to treat HIV, its neuropsychiatric effects are one of the primary reasons it is slowly being phased out in clinical situations.
Efavirenz: Interactions With Other Drugs
Efavirenz may interact with other drugs. Some common interactions include:
Etravirine and nevirapine
Taking efavirenz with these NNRTI drugs increases the risk of side effects.
This is a benzodiazepine medication used for anesthesia, as a sleep medication, and to decrease anxiety.
Taking efavirenz with midazolam decreases the metabolism of the latter resulting in an increased possibility for cardiac arrhythmias, prolonged sedation, and respiratory distress.
This is an antibacterial used to treat a variety of bacterial infections.
Taking clarithromycin with efavirenz reduces the levels of clarithromycin, resulting in a high incidence of rash.
Azithromycin may be used as an alternative drug.
Tramadol is a pain-relieving medication.
Taking tramadol with efavirenz may increase your risk of an irregular heart rhythm that may be life-threatening.
This is an anti-epileptic medication.
Taking efavirenz with phenytoin affects the levels of both medications in the blood.
This combination can reduce the level of efavirenz in blood, making the medication less effective.
Taking efavirenz with acetaminophen may increase the risk of liver damage.
When taken with co-trimoxazole, efavirenz may cause liver damage.
Sodium valproate is used to treat seizures.
Taking efavirenz with drugs like sodium valproate increases the risk of liver damage.
Can You Be Allergic To Efavirenz?
If you are allergic to efavirenz, you may experience symptoms like hives, skin rash, difficulty breathing or shortness of breath, fever, and burning eyes.
Genetics Of Efavirenz Allergy
The IL10 Gene and Efavirenz Allergy
The IL10 or the Interleukin 10 gene gives instructions for producing a protein that has anti-inflammatory properties.
rs1800896 is a single nucleotide polymorphism or SNP in the IL10 gene.
People with the TT genotype are at a greater risk of developing drug hypersensitivity when treated with efavirenz than those with the CT or CC genotypes.
Recommendations To Use Efavirenz
It is recommended to take efavirenz on an empty stomach.
Taking efavirenz with food increases the concentration of the drug in the blood and may increase the risk of adverse reactions.
Avoid drinking grape juice while taking efavirenz.
Studies say that a chemical in grape juice may increase efavirenz levels in the blood, resulting in more side effects.
Avoid consumption of alcohol with efavirenz as it may aggravate the adverse effects of efavirenz.
Medical and Medication History
Inform your doctor about any medical condition you may have and complete details of all the medicines and supplements you are currently taking.
This helps avoid drug interactions that often result in adverse effects.
- Efavirenz is a non-nucleoside reverse transcriptase inhibitor used as a first-line treatment for HIV.
- Apart from treating the condition, efavirenz also helps reduce the progression and transmission of the disease.
- Efavirenz works by preventing the reverse transcriptase process of the virus, decreasing the likelihood of developing AIDS and other related diseases.
- Common side effects of efavirenz include diarrhea, skin rash, nausea, abdominal pain, and headache.
- Efavirenz may precipitate severe side effects like nervous system problems, immune system changes, and psychiatric issues in some people.
- Due to its neuropsychiatric effects, efavirenz is usually phased out of treatment in most HIV patients.
- Inform your doctor about all medications and supplements you take to avoid any drug interactions and adverse effects.
- Some people may be allergic to efavirenz and must, therefore, avoid the drug.
- SNP rs1800896 in the IL10 gene is associated with allergy to efavirenz.
- Efavirenz is usually taken on an empty stomach to reduce the risk of adverse reactions.