July 25, 2008

Kaletra and Efavirenz Affect Prednisolone Levels

Blood levels of the anti-inflammatory drug prednisolone (Prelone) can decrease when combined with efavirenz (found in Sustiva and Atripla) and increase when combined with Kaletra (lopinavir/ritonavir), according to study results published online July 12 in the Journal of Acquired Immune Deficiency Syndromes. While these interactions are important to consider when prescribing prednisolone with either of these popular antiretrovirals, the authors also point out additional potential dangers: Rapid increases or decreases in prednisolone blood levels will likely occur among patients switching from efavirenz to lopinavir/ritonavir, or vice-versa.

Corticosteroids are used to treat a number of diseases and symptoms in which the immune system is inflamed, such as arthritis and asthma. The blood levels of one corticosteroid, fluticasone (Flovent, Flonase, Advair), which is commonly prescribed to treat allergies and breathing problems, are significantly altered by the protease inhibitor (PI) Norvir (ritonavir), a component of Kaletra and used in low doses to boost the blood levels of many other PIs.

In an effort to determine how antiretroviral (ARV) drugs impact the blood levels of the commonly prescribed oral corticosteroid prednisolone, Kristin Busse, PharmD, and her colleagues from the National Institutes of Health, first treated a small group of HIV-negative people with 200 mg of Norvir for two weeks and then gave them a single dose of 20 mg of prednisolone. They found that the Norvir increased the blood levels of prednisolone by 28 percent.

Busse’s team next enrolled a group of 30 HIV-positive patients—10 were on an ARV regimen containing efavirenz, 10 were on a regimen containing Kaletra, and 10 were not on any ARV drugs. All were then given a single dose of 20 mg of prednisolone following a light breakfast. Blood levels of prednisolone were checked at multiple intervals throughout the next 24 hours.

Busse’s team found that people who took Kaletra had slightly higher blood levels of prednisolone than people who took no ARV drugs, and that people who took efavirenz had slightly lower blood levels of prednisolone. Specifically, the maximum blood levels and total blood levels of prednisolone in people taking Kaletra were much higher than those taking efavirenz.

The authors, therefore, suggest that people with HIV who are taking both prednisolone and efavirenz should watch for prednisolone side effects when switching from efavirenz to Kaletra, and possibly to other Norvir-boosted PIs. Moreover, a rapid and profound drop in prednisolone blood levels—a possibility among patients switching from Kaletra to efavirenz—can lead to withdrawal symptoms, including joint pain, muscle pain, fever and low blood pressure. Here, too, the authors suggest careful monitoring.

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Jay, Tucker, 2008-07-30 13:54:30
I can testify to this. I began gaining a lot of weight quickly. After going to a endo doctor.. I had all the symptons of Cushing except The cortesol was extremely low in my body and he was confused. I used Advair and the Norviar and Presista increased the little bit of steroids in my system. I am still trying to get my girlish figure back... LOL