The Food and Drug Administration (FDA) recently approved Alli, a low-dose form of prescription drug Xenical, as an over-the-counter (OTC) weight loss aid for overweight adults.

No prescription required. Also not required: any mention of unpleasant side effects in DTC ads.

According the FDA, the “most common side effect of the product is a change in bowel habits, which may include loose stools.” A look at the Xenical Rx label reveals the details (click the image to enlarge):

Oily spotting, flatus with discharge, fecal urgency, and fatty oily stool … all occurred in more than 20% of patients taking Xenical in clinical trials according to this label.

Xenical sales, according to reports, has been dismal. “Will Diet Pill alli Succeed Where Prescription Diet Drug Xenical Failed?” That’s what one report asks:

“In the eight years that Xenical has been on the market, obese and overweight people around the world have tried the diet drug more than 25 million times. Yet, U.S. sales of Xenical peaked in the year 2000 at about $200 million, making it by any standards not a very successful prescription diet drug.

“By comparison, analysts are forecasting that prescription diet drug Acomplia (rimonabant) — on sale in Europe but still stalled at the Food and Drug Administation — may ultimately ring up annual sales as high as several billion dollars.” (See “Will Diet Pill alli Succeed Where Prescription Diet Drug Xenical Failed?“)

Ya think the Xenical side effects were to blame for the dismal sales compared to Acomplia?

Now that GSK is executing its Rx to OTC strategy with Xenical, will sales improve?

You bet they will!

And the reason they will is that finally GSK marketers can talk about the benefits without giving equal time (fair balance) to those unpleasant side effects. On the MyAlli Web site, side effect information is buried in press releases and watered down somewhat as in “Consuming a meal with too much fat, while taking alli, can result in bowel changes such as having an urgent need to use the bathroom.” You can find that buried in the 9th paragraph of the GSK press release.

If you click on “How Does It Work” and then find the “important safety information” link on that page and scan down below the page fold, you will find a few carefully wordsmithed phrases designed to tone down the shitty imagery somewhat:

  • gas with oily spotting
  • loose stools
  • more frequent stools that may be hard to control

Based on my study of print DTC ads (see “Print DTC: How Does It Measure Up?“), I expect the Alli ads in Oprah and other magazines to hide this information even better. In my study, exactly 0% of the OTC drug ads I studied mentioned any side effects at all!

I find it ironic that GSK/FDA point that these side effects can be minimized by eating a low-fat diet. Of course, if we all did that we wouldn’t need an Alli in the first place.

Of course, you could always pick up a box of Depends at the next counter over when you purchase your Alli at the drug store.