The World Health Organization (WHO) on Monday issued revised guidelines for millions of people infected with HIV, the virus that causes AIDS.
Here are the major recommendations by the United Nations agency which has 193 member states:
* Countries should phase out use of Stavudine, the most widespread antiretroviral, because it has "long-term, irreversible" side-effects including wasting and a nerve disorder.
U.S. drugmaker Bristol-Myers Squibb Co and India's Cipla and Aurobindo Pharma Ltd are among leading producers.
* Instead, countries should use two other antiretrovirals -- Zidovudine (AZT) or Tenofovir (TDF) -- which are less toxic and equally effective.
* HIV patients, including pregnant women, should now start antiretrovirals earlier, when their CD4 count, a measure of immune system strength, falls to 350 cells/mm3, regardless of symptoms.
* WHO's previous guidelines, issued in 2006, called for starting treatment when patients' CD4 count falls to 200 cells/mm3 -- when they typically show symptoms of HIV disease.
"The best time to start ART (antiretroviral therapy) is before patients become unwell or develop their first opportunistic infection," the WHO said, referring to diseases such as tuberculosis which prey on weakened immune systems.
* To prevent mother-to-child transmission, HIV-positive pregnant women should start using the drugs from 14 weeks into pregnancy, rather than 28 weeks as previously recommended, and continue until the end of breastfeeding.
"For the first time, there is enough evidence for WHO to recommend antiretrovirals while breastfeeding," it said.
* Breastfeeding should continue until the infant is a year old, providing both mother and child take the drugs. "This will reduce the risk of HIV transmission and improve the infant's chance of survival."
Without treatment, one third of the children living with HIV die before their first birthday and almost half by the second year, the Geneva-based agency said.
(Compiled by Stephanie Nebehay, edited by Tim Pearce)