An effective antiretroviral treatment blocks the spread of HIV in the body by inhibiting the production of of new HIV particles.By inhibiting the replication of HIV the deterioration of the immune system is stopped and even reversed to a normally functioning immune system over time. This has stopped HIV infected people under effective HIV therapy from dying due to HIV associated complications. In addition HIV infected people under effective therapy do not transmit the virus by sexual contact anymore.

In general, it is never too late for antiretroviral therapy, but the later the treatment is started the more the immune system is already impaired. When starting late during a transition period there is an increased risk of opportunistic infections until the resolution of the immune deficiency.

The current recommendation is to offer antiretroviral therapy to every HIV infected patient regardless of helper cell count (CD4+ cells) and viral load (HIV RNA). Apart from preventing HIV associated diseases inhibiting transmission of HIV by effective antiretroviral therapy is an important reason. However, personal preferences when to start can be taken into account as long as there is no urgent need due to advanced immune deficiency.

Indications for an immediate start of antiretroviral therapy are:

• symptoms associated with HIV infection such as fever, night sweats, loss of weight, persistent swelling of lymph nodes and other symptoms
• permanent reduction of the absolute helper cell count to less than 350 cells per microliter or sustained reduction of relative helper cells below 15 %

If the absolute helper cell count is less than 200/µl or if the relative count declines to less than 15 % the risk of life-threatening opportunistic diseases is high.

In this situation, it is essential to begin antiretroviral therapy as soon as possible to improve the immune system and to prevent opportunistic infections. Specific prophylaxis of opportunistic infections should be initiated and continued until the resolution of the severe immune deficiency.

Antiretroviral therapy is generally considered life-long. Planned interruptions are possible in specific situations. Curing HIV is not yet possible to date, but long term antiretroviral therapy offers the perspective of a near normal life expectancy despite HIV infection.