New studies are fine-tuning our knowledge of HAART side effects. Consider the damage done to the liver by the protease inhibitor (PI) ritonavir (Norvir) and to the lungs by the nucleoside analog (nuke) abacavir (Ziagen). It’s long been known that antiretrovirals are hard on the liver, but recent research suggests that some meds are especially risky. In a two-year study of 298 HIVers—211 on PI-containing combos, and 87 on dual nukes only—the overall occurrence of severe liver toxicity was 10 percent. But three times as many using ritonavir, with or without second PI saquinavir (Fortovase), had the problem. The risk of severe toxicity with dual-nuke regimens was similar to that seen with combos containing indinavir (Crixivan), nelfinavir (Viracept) or saquinavir without concurrent ritonavir—all around 6 to 7 percent.
What about abacavir? At approval, it was known that 5 percent of those taking it had a hypersensitivity reaction (severe allergic response). Users were warned to suspect this if they developed a skin rash or two or more of the following sets of symptoms: fever; nausea, vomiting, diarrhea or abdominal pain; severe fatigue, achiness or a generally ill feeling. Now add: coughing, sore throat and shortness of breath—nonspecific symptoms that can be misdiagnosed as flu. These occurred in about one-fifth of those with the hypersensitivity reaction, or 1 percent of all those on the drug. So anyone who fits this bill is advised to stop abacavir and call their doc ASAP. Once discontinued, the drug can’t be restarted. (Note: Getting yearly flu vaccines may help avoid symptoms that could be mistaken for an abacavir lung attack.)