Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

Sign Up

HIV & AIDS Health Center

Font Size

Quick, Simple Test Could Reduce HIV Drug Resistance

WebMD Health News

Nov. 22, 2001 -- Knowing whether HIV drugs are working can ultimately mean the difference between life and death. Assessing drugs' effectiveness currently takes as long as two months, but findings reported this week by researchers from two federal health agencies suggest the process can be shortened to as little as a week.

Researchers from the National Institute of Allergy and Infectious Diseases (NIAID) and the National Cancer Institute found that the rate at which the AIDS virus disappears from the blood during the first week of treatment is a highly accurate measure of whether the drugs will fail. The report was published in the Nov. 24 issue of the medical journal The Lancet.

The preliminary research indicates that people who do not experience a five-fold, or 80%, drop in viral load by the sixth day of treatment will almost certainly have a poor long-term response to the chosen drugs.

"We found that if we didn't see a rapid drop in viral load during the first week, then there was a good chance that the drug regimen was not going to be effective," lead author Michael A. Polis, MD, of the NIAID, tells WebMD. "If we don't see a big drop, then it could mean that a patient isn't taking the drugs appropriately or it could mean resistance. Either way, the earlier we know this the better."

If confirmed and widely adopted, the simple measure could reduce drug resistance among people on HIV drugs. Side effects of treatment might also be minimized if doctors can more rapidly identify drug treatments that don't work.

There are currently around 17 different HIV drugs that have been approved by the FDA. They are given in a variety of combinations, because the fast-mutating virus quickly develops resistance to single drugs. Because many of the drugs are similar, resistance to one drug may mean resistance to several.

The most common way to test how well HIV drugs are working is by measuring the amount of virus in the blood after four to eight weeks of therapy. Using data from three previously reported trials, Polis and colleagues found that the five-fold or less drop in viral load at day six of therapy predicted treatment failure more than 99% of the time.

Today on WebMD

How much do you know?
contemplative man
What to do now.
Should you be tested?
HIV under microscope
What does it mean?
HIV AIDS Screening
man opening condom wrapper
HIV AIDS Treatment
Discrimination Stigma
Treatment Side Effects
grilled chicken and vegetables
obese man standing on scale
cold sore