Efavirenz is intended for the treatment of HIV infection. This medication helps lessens the quantity of HIV in your body. It is to let your immune system function well. This lowers your chance of getting HIV complications and improves your quality of life. The Food and Drug Administration (FDA) has already approved this medication. Efavirenz comes as a tablet for oral use. Each tablet has a dosage strength of 600 mg. 

HIV infection is a sexually transmitted infection. This infection can also spread by contact with infected blood or from mother to child during pregnancy, childbirth or breastfeeding. Most people infected by HIV develop a flu-like illness within a month or two after the virus enters the body. This disease identified as acute HIV infection may last for a few weeks. Possible signs and symptoms include:

• Headache
• Fever
• Rash
• Muscle aches and joint pain
• Swollen lymph glands mainly on the neck
• Sore throat and painful mouth sores

As the virus remains growing and destroying your immune cells, the cells in your body that help fight off germs. You may progress minor infections or chronic symptoms such as:

• Fatigue
• Fever
• Diarrhea
• Swollen lymph nodes often one of the first signs of HIV infection
• Weight loss
• Oral yeast infection 
• Shingles or herpes zoster

Risk factors of HIV may include:

• having another sexually transmitted infection (STI) such as herpes, syphilis, gonorrhea, chlamydia, and bacterial vaginosis;
• having unprotected anal or vaginal sex
• blood transfusions receiving unsafe injections, and tissue transplantation, and medicinal processes that consist of unsterile piercing or cutting 
• sharing contaminated syringes, needles, and other injecting equipment and drug solutions when injecting drugs
• experiencing accidental needle stick injuries including among health workers

How does Efavirenz work?

Efavirenz is a type of medicine called a non-nucleoside reverse transcriptase inhibitor. Acquired Immune Deficiency Syndrome (AIDS) is caused by infection with HIV. This virus invades cells of the immune system. Particularly, it is the white blood cells known as CD4 T-helper lymphocytes. These cells usually work to activate other cells in the immune system to fight infection. Since HIV kills CD4 T-helper cells, over time the body becomes less able to fight the virus or subsequent infections. Once the virus is inside the CD4 T-cell, it multiplies. Part of the process of viral multiplication involves the conversion of the virus genetic material, RNA, into DNA. This is attained by a multiple important to the virus called reverse transcriptase. It is a compound known as an enzyme. 

Efavirenz works by blocking the action of this enzyme. This medicine blocks the enzyme in a slightly different way. Blocking the action of the enzyme interferes with the conversion of viral RNA into DNA, which stops the virus from multiplying.

A combination of several anti-HIV medications is necessary to fight HIV because the virus can become resistant to one agent very fast. This is known as cART (combined antiretroviral therapy) or HAART (highly active antiretroviral therapy). Consuming medications that work in unalike ways together helps avoid resistance from happening. 

How to use Efavirenz?

Take this medication by mouth on an empty stomach. Efavirenz is usually taken once a day at bedtime as directed by your doctor. Taking this drug with food increases the blood level of this medication. It may increase your risk of certain side effects. 

Swallow the tablet as a whole with a full glass of water. Do not crush, break, or chew it. The dosage is based on your medical condition and response to the treatment. Be sure to tell your doctor about all the products you use. The continuous taking of this medication exactly as it is prescribed by your doctor is very important. Do not increase your dose, take this drug more often than prescribed, or stop taking it even for a short time unless directed to do so by your doctor. Changing or skipping your dosage without approval from your doctor might cause the quantity of virus to increase. It may as well make the infection harder to treat or let side effects get worse. 

What are the side effects of Efavirenz?

Common side effects:

• Trouble sleeping or insomnia
• Dizziness
• Unusual dreams
• Drowsiness
• Nausea
• Vomiting
• Trouble concentrating 
• Diarrhea
• Stomach pain
• Blurred vision
• Cough
• Headache
• Tired feeling
• Spinning sensation
• Problems with balance or coordination
• Muscle or joint pain

Tell your doctor right away if you have these side effects:

• Stomach or abdominal pain
• Persistent nausea or vomiting
• Severe tiredness
• Dark urine
• Yellowing eyes or skin

Warnings and Precautions 

• It is recommended that you avoid drinking grapefruit juice while taking Efavirenz. It may increase your exposure to Efavirenz and increase the risk of its side effects.
• While having this medication, avoid potentially hazardous activities such as operating machines or driving.
• People taking antiretroviral medicines may gain weight and may also experience increases in the levels of sugar and fats in their blood. However, these changes are in part linked to the improvement in control over your HIV and your lifestyle.
• Some people being treated with combination antiretroviral therapy may develop a bone condition called osteonecrosis. This condition is caused by loss of blood supply to a bone, causing the death of the bone tissue. If you notice any aches and pains, joint stiffness, or difficulty in movement while using this medicine, you should tell your doctor so this can be checked. 
• This medicine can sometimes cause kidney problems. Your kidney function should be monitored before starting and regularly throughout treatment with this medicine. Your doctor may want to monitor your kidney function more frequently if you already have, or are at risk of kidney problems. 
• Use Efavirenz with caution in people over 65 years of age, people with liver disease, with a history of psychiatric illness or fits. 
• This medication should not be used in people with decreased kidney function and decreased liver function. 
• This is not recommended for use in people who have had a life-threatening skin reaction. 
• Let your doctor know if you are breastfeeding, pregnant, or planning to become pregnant. 
• Call for medical assistance right away if you have any signs of an allergic reaction. Let your doctor know if you have any allergies as well.