Brand Name: Norvir

Common Name: ritonavir (RTV)

Class: HIV protease inhibitor

Standard Dose: Almost never used at its approved dose (a lead-in dosing, then six 100 mg soft gelatin capsules twice-a-day, preferably with food—dose escalation is important to avoid side effects). Norvir is primarily used as a boosting agent for other PIs, at smaller doses of 100 to 400 mg, either once or twice a day. Take a missed dose as soon as possible, but do not double up on your next dose. Approved for children ages one month and older. Liquid formula available, but tastes unbelievably horrific.

AWP:$321.46 / month for 30 capsules

Manufacturer contact: Abbott Laboratories,
www.norvir.com, 1 (800) 222–6885

AIDSInfo:1 (800) HIV–0440 (448–0440), www.aidsinfo.nih.gov

Most common side effects include: weakness, stomach pain, upset stomach (nausea, diarrhea, and vomiting), tingling/numbness around the mouth, hands or feet, loss of appetite, taste disturbance, weight loss, headache, dizziness, pancreatitis (see nukes), and alcohol intolerance.

As seen with other protease inhibitors, there can be increased levels of cholesterol and triglycerides (except possibly unboosted Reyataz) which may be associated with an increased risk of heart disease. Other possible side effects are lipodystrophy (body fat changes, including thinning of the face, arms and legs, with or without fat accumulation in the stomach, breasts and sometimes the upper back), onset of new cases or worsening of diabetes (see your doctor promptly) and increased bleeding in hemophiliacs.

Other potential side effects are liver problems, such as increase in liver enzymes (AST, ALT and GGT), hepatitis, or jaundice (yellowing of skin); and increased muscle enzyme (CPK) and uric acid. People with hepatitis B or C may be at increased risk.

Ritonavir interacts with many other drugs. See the manufacturer package insert for the most complete list. Do not take with Tambocor, Rythmol, Cordarone, Versed, Halcion, Rifadin, Orap, ergot derivatives (such as Cafergot, Wigraine and Methergine, D.H.E. 45), Antabuse or Flagyl, garlic supplements, or the herb St. John’s wort. Do not use Zocor or Mevacor; lipid-lowering alternatives are Lipitor, Lescol, and Pravachol, but they should be used with caution due to potential for liver toxicity.

Protease inhibitors increase blood levels of Viagra, Cialis and Levitra. Use with caution. Initially the Viagra dose should be 12.5 mg (1/2 of 25 mg tablet) and increased as needed and tolerated. It’s recommended that people on PIs do not exceed 25 mg of Viagra in a 48-hour period because of potential for serious reaction such as low blood pressure, visual changes, and prolonged erection leading to permanent tissue damage. Use Cialis at reduced doses of 10 mg every 72 hours and Levitra at reduced doses of no more than 2.5 mg every 72 hours, with increased monitoring for adverse events.

The effectiveness of birth control pills may be decreased when taking Norvir; women and their male partners should consider the use of alternative contraception methods with barrier.

Levels of the street drug Ecstasy are greatly increased by Norvir, and at least one death has been attributed to the combination. GHB is also dangerous with Norvir. Tobacco and alcohol may lower blood levels of Norvir. Increases seen in clarithromycin (Biaxin) levels by 80 percent. Rifampin decreases Norvir levels by 35 percent. Contains alcohol (but should not be enough to trigger relapse), so be cautious with Antabuse or Flagyl—greatly hastens intoxication.

The real strength of Norvir is in combination with other PIs (used as a boosting agent), allowing for a lower dose of both. Stomach side effects are reduced by taking Norvir with high fat foods (such as peanut butter or avocado)—however, be careful because some other HIV medicines should not be taken with high fat foods. You can mix liquid solution in ice cream, milk or pudding to hide the bitter taste. The capsules contain castor oil and have bitter taste. Chocolate masks the bitter taste. Plasma concentration increases in people with hepatic (liver) impairment.

Except in the most severe of salvage situations, this drug is almost never used at full dose, and is almost exclusively used as a “booster” for other antiretrovirals now. Because it blocks a certain pathway in the liver that metabolizes many HIV drugs (particularly PIs), it causes levels of other drugs to stay higher longer, which is great because that means that with most of the drugs we can take less pills and get the same effect. Norvir has a whole host of side effects (some of them pretty bad) which are significantly lessened and often not an issue with the booster dose of 100 mg, yet some people still have trouble taking any Norvir at all. Unfortunately there are no other drugs our there that have this same boosting effect, so we are stuck with this one for a while. The company that makes this drug Abbott Laboratories made a decision a few years ago to raise the price of this older PI by 400% which outraged community and medical professionals alike, and they are still trying to live it down. Ultimately the utility of this drug cannot be denied, and it has helped to make treatment better overall by reducing the need for large numbers of pills in many cases and allowing once daily dosing of several PIs.

But was it worth it to raise the price by four hundred frigging percent? (I could not call myself an activist and not mention that here). Come on, we are not idiots; we know what that decision was all about. But alas, now we are ready to move on. It’s about time for another company to develop a better booster. Anybody up for the challenge?—Cathy Olufs