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June 25, 2008


Antiretroviral Therapy

The goal of antiretroviral therapy is to prevent HIV from replicating (making more copies of itself). The antiretroviral drugs that are currently available belong to four classes: nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), and entry inhibitors.

Each class of antiretroviral drugs fights HIV in a unique way. NRTIs (such as AZT and tenofovir) and NNRTIs (including Sustiva and nevirapine) interfere, in different ways, with the production of reverse transcriptase, a protein the virus must use in order to replicate. PIs (such as Kaletra and saquinavir) interfere with HIV's use of the protease enzyme, another component essential to its replication. Finally, the entry inhibitor Fuzeon prevents HIV from entering cells and making more copies of the virus.

Highly active antiretroviral therapy (HAART) combines three or more drugs from among the four classes (e.g., two NRTIs and one PI). This is very important, because the virus in an HIV-positive person's body can change after exposure to antiretroviral medications and become resistant to certain drugs, making those drugs less effective for that particular person. A treatment regimen that involves taking medications from more than one class at a time has a built-in safety net: if the virus becomes resistant to a drug from one class, then drugs from the other classes can continue to fight the virus.

In addition, some drugs are now combined in one pill; for example, Combivir, Trizivir, Epzicom, and Truvada combine two or more NRTIs in a single pill. As a result, some treatment regimens require patients to take as few as four pills per day, making it easier for HIV-positive people to adhere to their drug regimens.

HAART has been credited with significantly improving the length and quality of life for many people living with HIV/AIDS. In addition, new drug classes and medications to fight HIV are currently being developed so that people with drug-resistant HIV have more treatment options.

See a list of currently approved antiretroviral medications.

In addition, the U.S. Department of Health and Human Services (DHHS) issues guidelines for the medical management of HIV infection and issues surrounding HIV infection, including treatment in adults, adolescents, and children. Learn more about these guidelines. (

Project Inform -- a national HIV treatment organization based in San Francisco -- also provides excellent information and materials on a range of HIV treatment issues. In addition, these treatment links can also help you better understand your treatment options and make informed choices about your HIV care.

Seeking Care for HIV Disease

It is important for people who are HIV positive to seek regular care from a physician. Such care will provide you with important information about the progression of your disease and will assist you in deciding whether to start taking antiretroviral medications.

Selecting a Doctor

The first step in getting care for HIV/AIDS is to choose a physician. Obviously, it is best to find a doctor who is familiar with treating HIV disease. Doctors who don't specialize in HIV treatment are not likely to keep up with rapidly changing developments in drug therapies and treatment strategies.

It is always okay to get a second opinion if you have doubts about a doctor's approach to treating HIV. In fact, some people "interview" several doctors before making a permanent selection.

To search online for an HIV/AIDS specialist in your area, visit the American Academy of HIV Medicine or the HIV Medicine Association.

Monitoring Your HIV Health

Your overall health and HIV disease progression are reflected in the health of your immune system. HIV impairs immune function by infecting certain white blood cells -- called CD4 cells -- that normally help keep the immune system working. HIV uses CD4 cells as a tool to replicate, or make copies of itself: the virus enters the CD4 cell, gives it "instructions" for making more HIV instead of helping the immune system, and finally destroys the CD4 cell. When CD4 cells are lost, the immune system is weakened.

Even for an HIV positive person who is asymptomatic (without symptoms), it is very important to monitor the immune system in order to make the best choices about treatment. Two tests are used to monitor immune health:

  • CD4 count test: an immune monitoring test (also called a T4 or helper T cell count test) that measures the number of CD4 cells in a blood sample. This is typically expressed as number of CD4 cells per cubic millimeter (mm3). CD4 count is one indicator of how much damage HIV has caused to the immune system: a higher CD4 count means less damage. A single CD4 count test does not say much about one's general health. The trend over time provides a better sense of immune health by indicating whether CD4 count is stable or declining. It is only possible to determine a trend after three tests, generally three to six months apart. For an accurate picture of immune health and disease progression, it is essential to also monitor one's viral load.
  • HIV viral load test: a test that measures the amount of HIV genetic material (RNA or DNA) in the blood. Viral load is often expressed as number of copies per milliliter (mL). Two types of viral load test are currently available, and they measure viral load in different ways. One test, called the branched-chain DNA (bDNA) test, measures viral load by causing the viral RNA in a sample to emit (give out) light; more light means that more virus is present in the patient's blood. The other test, called the reverse transcriptase polymerase chain reaction or RT-PCR test (commonly called PCR), chemically multiplies the amount of viral RNA in a blood sample, which makes it easier to estimate the amount of virus in the body. A single viral load test is not very meaningful; it must be considered along with other tests, such as CD4 count, or compared to past viral load tests to be helpful as an indicator of disease progression and immune health.

Another important diagnostic tool is resistance testing, which helps determine whether an HIV-positive person's specific virus is resistant to certain anti-HIV medications, rendering those medications ineffective for that person. With this knowledge, the individual and his or her physician can avoid those medications when customizing a treatment regimen. There are two different resistance tests:

  • Genotypic test: a resistance test in which a sample of the virus is taken from an HIV-positive individual and its genetic structure is examined for mutations that make it resistant to a specific drug.
  • Phenotypic test: a resistance test conducted on genetic copies of the virus taken from the HIV-positive individual. How the copies react to anti-HIV medications indicates whether the individual's virus is resistant to those drugs.

Other tests and general diagnostic tools, such as CBC (complete blood count), help physicians gain more information about how the immune system is responding, in terms of both disease progression and treatment.

People with health insurance can usually get most of these tests through private doctors, clinics, or hospitals. For people without health insurance, programs at community clinics and county public health departments often provide some or all of these tests at reduced cost or free of charge.

When to Begin Antiretroviral Treatment

There are varying opinions on when is the best time to begin HIV treatment; however, the federal Centers for Disease Control and Prevention (CDC) recommends starting highly active antiretroviral therapy (HAART) if you have a history of opportunistic infections (OIs) or other severe symptoms of HIV disease, or if your CD4 count is lower than 200/mm3. The CDC also suggests that you may want to consider starting HAART if your CD4 count is lower than 350/mm3 and your viral load is greater than 100,000 copies/mL, even if you are not experiencing symptoms of HIV disease. Preventive treatment (prophylaxis) against Pneumocystis carinii pneumonia and other OIs is recommended when CD4 count indicates severe immune suppression.

Treatment is a personal choice and when or if you start can depend on a variety of other health issues. It is helpful to find a doctor you trust who can help you determine what treatment strategy makes the most sense for you.

These treatment links can help you make informed decisions about starting antiretroviral therapy.

Opportunistic Infections

HIV positive people with suppressed immune systems may experience illnesses that are not usually seen (or do not cause symptoms) in people with healthy immune systems; these illnesses are called "opportunistic infections" (OIs). Some of the most common OIs include:

  • Pneumocystis carinii pneumonia (PCP): a life-threatening type of pneumonia caused by a protozoan (a single-celled organism). PCP is usually seen only in people in the advanced stages of HIV disease. It is much less common in people with HIV since the advent of HAART.
  • Mycobacterium Avium Complex (MAC) disease: is among the most common bacterial infections in people with HIV. These bacteria are found in water, dust, soil and bird droppings. They enter the body in food and water or sometimes through the lungs. A weakened immune system allows the bacteria to attack the lining of the gut and multiply.
  • Cytomegalovirus (CMV): a herpesvirus that may cause serious disease, including retinitis (inflammation of the retina), pneumonia, colitis (inflammation of the large intestine), and encephalitis (inflammation of the brain), in individuals with extremely weakened immune systems.
  • Tuberculosis (TB): a potentially fatal infectious disease caused by Mycobacterium tuberculosis. TB typically affects the lungs, but may also occur in other organs.
  • Toxoplasmosis: an OI caused by the Toxoplasma gondii protozoan, most commonly found in cat feces and undercooked meat. Early signs of toxoplasmosis include fever, confusion, headache, tremor, disorientation, personality changes, and seizures.
  • Candida: a type of yeast-like fungi. Some Candida species are normally found in the mouth, intestines, and vagina, but can overgrow and cause disease (candidiasis, or thrush) in people with compromised immune systems.
  • Cryptosporidiosis: a disease caused by the protozoan Cryptosporidium parvum, which is transmitted by contact with animal feces, ingestion of contaminated food or water, or oral-anal sexual contact (rimming). Cryptosporidiosis can cause weight loss, swollen or tender lymph nodes, and severe, chronic diarrhea.

Many OIs can be prevented or treated successfully. This has substantially increased the longevity and quality of life for people living with HIV/AIDS. The U.S. Department of Health and Human Services (DHHS) issues guidelines for the medical management of HIV infection and issues surrounding HIV infection, including treatment and prevention of OIs. To learn more about these guidelines for treating OIs, go to or

Clinical Trials

Clinical trials test drugs that are promising but have not yet been proven effective. Each new drug must go through several phases of clinical trials to determine toxicity (whether the drug is harmful) and efficacy (whether the drug is effective).

Most clinical trials have strict eligibility rules. Eligibility criteria often include viral load, CD4 count, current or previous symptoms and opportunistic infections, antiretroviral drugs taken in the past and current drug regimen.

It is important for people who choose to participate in a clinical trial to feel fully informed about the trial and comfortable with its rules, as well as with the physicians and researchers who are carrying it out. Participants should also know they have the right to leave a clinical trial at any time and for any reason.

Learn more about clinical trials at or, or by reading this BETA article.

Natural Approaches to Treating HIV

Many HIV-positive people believe contemporary or "Western" medicine is most appropriate for treating illness. Others feel that "alternative" medicine is more appropriate, or that it complements Western treatments. Complementary and alternative approaches include herbal or Chinese medicine, holistic medicine, spirituality, body work, relaxation techniques, and many others. For some, a combination of Western and alternative approaches helps the body fight toxicity and immune suppression.

Natural approaches to wellness are as diverse as each person's cultural background, life experience, and individual metabolism. As with other treatment considerations, it is best to seek advice from a doctor you trust. Also, be sure to inform your doctor of any alternative medicines or supplements (including vitamins and herbs) you are taking, as these may affect how your body responds to a particular anti-HIV medication.


With HIV disease, the immune system is under great stress. Eating a balanced diet that includes a variety of foods can help strengthen the immune system and maintain optimum body weight. A balanced diet is based on selecting foods from the four basic food groups: proteins, fruits and vegetables, breads and grains, and dairy products.

People with HIV disease are encouraged to eat a balanced diet high in protein and calories, which the immune system requires to fight illness. Most people with symptoms of HIV disease need up to 3,500 calories per day. They may also have one and a half to two times the normal protein requirement of other people -- as much as 130 grams per day. For an overview of nutrition for people with HIV, read this Winter 2006 BETA article.

Because some AIDS-related conditions affect the ability to eat and some treatments have dietary restrictions, it is important to consult a physician and an HIV-knowledgeable dietitian to ensure adequate nutrition. The Association of Nutrition Services Agencies provides nutrition education for people with HIV/AIDS at

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This article was provided by San Francisco AIDS Foundation. It is a part of the publication AIDS 101. Visit San Francisco AIDS Foundation's Web site to find out more about their activities, publications and services.