by Derek Thaczuk
Different meds have different resistance profiles, dosing, drug interactions and side effects. You and your doc can navigate the differences and make a choice that’s best for you.
With several tried-and-true HIV meds to choose from, it’s time to focus on the options that might be best for you. This requires knowing about how the top-notch ARVs are similar in terms of their activity against drug-resistant virus, their daily dosing, interactions with other ARVs and meds used for other diseases, and side effects.
The first step in picking the right meds is knowing whether or not your virus is resistant to any drugs. Virus resistant to one or more ARVs can be passed from person to person and can emerge while on therapy. Resistance to any drug generally takes it off your list of possibilities. Benjamin Young, MD, of Denver’s Rose Medical Center, says that drug-resistance testing can be useful before treatment has been started; it can also help map out the best new options for those with an existing treatment history. By identifying which meds your virus is resistant to, you can avoid a situation where you are taking meds that will have no positive impact on your health.
Another important consideration is dosing. Taking hand–fuls of pills multiple times a day used to be the norm. Today, dosing is much less of an issue. “[All regimens] are once or twice a day now,” says Dr. Young. “You’re looking at a maximum of five pills per day.”
Fixed-dose combinations like Truvada and Epzicom cut down on pill burden by packing multiple meds into single pills. The easiest of them all is Atripla—Davis’s choice—a one-pill complete daily regimen containing efavirenz, tenofovir and emtricitabine. However, it’s by no means a solution for everyone: Dr. Martorell has patients “who come in and say, ‘I want Atripla.’” Yet, because of factors like drug resistance, “some people are not candidates for the medication they think they want. [In those cases] I try to explain why that may not be the best option, and give them others to choose.”
While drug interactions aren’t usually at the top of every–one’s minds, they should be. Meds can play off each other, potentially boosting each other’s levels—sometimes to toxic degrees—or lowering them with the danger of treatment failure and drug resistance.
Sometimes, interactions can be put to good use. The older PI Norvir (ritonavir), too toxic at the six capsules twice daily needed on its own, is now used at much lower doses to boost the blood levels and effectiveness of newer, more palatable PI options.
The Norvir needed for PI boosting tends to mean extra pills. Kaletra avoids that problem by packing lopinavir and ritonavir into the same tablet, allowing for a total of four PI pills daily (DHHS prefers two tablets twice daily but lists four tablets once a day as an alternative). Kaletra, however, includes 200 mg of ritonavir a day; lower-dose Norvir boosting is possible with the other DHHS-preferred boosted PIs.
Norvir-boosted Reyataz (atazanavir) is only FDA-approved for those who have been on treatment or for anyone also using Viread or Truvada (tenofovir in these meds lowers Reyataz levels in the blood, requiring the ritonavir boost). The DHHS prefers that anyone using Reyataz also use a Norvir booster, at a dose of 100 mg Norvir plus a 300 mg Reyataz capsule.
Boosted Lexiva is taken as two 700 mg tablets every day, either separately every 12 hours, which is preferred by the DHHS, or together every 24. Twice-daily Lexiva requires one 100 mg Norvir capsule twice a day. If you go the once-a-day route, one 100 mg Norvir capsule is all that’s needed.
Norvir, however, is known for its propensity to interact with other meds. Regardless of which Norvir booster dose you’re on, the result is the same—potentially dangerous interactions with other meds, including migraine treatments, cholesterol-lowering drugs, erectile dysfunction pills and herbal remedies.
Some PIs also interact problematically with other meds, regardless of whether or not they are being boosted by Norvir. Reyataz, for example, needs to be used very carefully with proton pump inhibitors (examples include Nexium, Prevacid and Protonix) and H2-receptor antagonists (including Tagamet, Pepcid and Zantac)—all used to treat heartburn and acid reflux. Because Reyataz needs stomach acid to be absorbed properly, these meds can sabotage your treatment if strict dosing instructions aren’t followed.
Sustiva and Atripla can also interact unfavorably with certain meds.
Young warns that drug interactions can get quite complicated. Your best bet is to be sure your doctor is aware of all the prescription meds, over-the-counter products, supplements and street drugs you’re taking, so that he or she can help you select your ARVs carefully.
Sidestepping Side Effects
All HIV medications have the potential to cause side effects. “[But] the idea that you have to suffer for success is an old-testament view,” says Young. “We now have meds that can be very well tolerated and cause few or no side effects or longer-term complications. We may not achieve that in 100 percent of our patients, but that’s our objective and we get very close to it in most people.”
Knowing which medications cause what side effects can help guide your choices and prepare you to handle those side effects if they arise. Don’t be afraid to raise questions or concerns about side effects with your health care provider before and during treatment. For more help, log on to AIDSmeds.com to learn about
the side effects associated with specific ARVs.
The side effects of efavirenz in Sustiva and Atripla tend to be different from those seen with most other ARVs. They include dizziness, feeling disoriented, vivid dreams and depression. If they occur, these central nervous system effects are tolerable and usually go away within a few weeks. For some, the problems can be serious enough to warrant stopping or switching therapy.
PIs share several side effects, especially since they’re often administered with Norvir. Gastrointestinal problems—stomach upset, nausea and diarrhea—are typical of Norvir-boosted PIs. PIs as a class also tend to raise blood lipids like cholesterol and triglycerides.
Don’t paint all boosted PIs with the same brush, though. “Recent developments in the use of lower-dose Norvir have resulted in regimens that have lower pill burden and improved tolerability,” says Young. While clinical trial data haven’t yet confirmed the suggestion, the risk and severity of Norvir-related side effects may be lessened with regimens that rely on the lowest possible booster dose—an option with Reyataz and Lexiva, but not Kaletra (Kaletra’s two-in-one fixed-dose formulation prevents lowering the Norvir dose).
PIs can also have unique side effects, regardless of whether or not a Norvir booster is used. Reyataz, for instance, interferes less with lipids than other PIs do (although levels can increase when Norvir is used). It can also increase blood levels of the liver by-product bilirubin, leading to jaundice—a yellowing of the whites of the eyes, nails and skin.
Martorell confirms that the problem is purely cosmetic and that it’s not a sign of liver damage. She cautions, however, that visible jaundice can be an issue for people who work in the food industry, where hepatitis (another condition that produces jaundice)—perceived or otherwise—is taken very seriously.
“If my side effects had been unbearable,” Davis says, “I would’ve switched. I know people on all the different [ARVs] and they’ve chosen them [over other meds] for various reasons—they don’t want the dreams, the diarrhea or pills twice a day. Everybody’s got their own reasons.”
Martorell applauds people who are involved in their own health care and urges doctors to listen up. “If you want your patient to be successful,” she says, “it’s important to listen to what the patient needs.”
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