Friday Favorites: Removing Warts with Duct Tape

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

You can find home remedies for all sorts of ailments, but the science doesn’t always back them up. What does it say about using a common household product on warts?

When I was reviewing the science behind common over-the-counter remedies used in dermatology, such as tea tree oil for acne or nail fungus, I was surprised to see on the same page a section on duct tape. Duct tape?! The only time I remember seeing duct tape used in a medical study was on the “[i]dentification of the gases responsible for the odor of human [farts],” which involved a collection system comprised of “gas tight pantaloons…sealed to the skin” with duct tape. (That’s the study where they assessed the wind-breaking ability of a cushion called the “Toot Trapper.”)

But what the dermatology journal was talking about is warts. “Duct tape brings out our inventive, slightly kooky side.” “Given this versatility, it wasn’t so surprising a few years ago when a group of doctors…reported that duct tape could get rid of warts.” As I noted in my last wart video, all sorts of strange things are purported to cure warts, because most go away on their own. A thousand kids were followed for two years, and two-thirds of the warts disappeared without doing a thing. So maybe we should just leave them alone—”although there are cases [that] may warrant treatment.” Otherwise, we can just let our own body take care of them.

Warts are caused by wart viruses, and so, spontaneous wart disappearance is assumed to be an immune response, where our body finally wakes up and takes notice. This assumption is based on studies like this, where foreign proteins were injected into the wart itself—like a measles-mumps-rubella vaccine straight into the wart, which compared to placebo, appeared to accelerate the immune clearance process. The problem, of course, is that injections hurt, and 30 percent of the kids that got their warts injected with the vaccine suffered a flu-like syndrome. Yikes! Okay, scratch that. What else do we got?

Within a few months, any placebo treatment will work in about a quarter of the cases. So, if you put duct tape on 100 warts, and 23 went away, that wouldn’t mean much. The traditional medical therapies—acid treatments and freezing treatments—bump the cure rate up to about 50 percent. So, if you were really serious about testing the efficacy of duct tape, you would pit it head to head against one of those. And that’s exactly what happened. “The efficacy of duct tape vs cryotherapy in the treatment of…(the common wart).” Cryotherapy is the current treatment of choice for many pediatricians.

“Objective: To determine if application of duct tape is as effective as cryotherapy in the treatment of common warts.” Patients were randomized to receive either liquid nitrogen applied to each wart, or “duct tape occlusion.” When I heard about treating warts with duct tape, I had this image where they were like trying to rip them off or something. But no; they are just applying a little circle of duct tape every week or so. Here are the details.

Although there had been a few anecdotal reports of using tape, “no prospective, randomized controlled trial had yet [been] performed,” until this study, which found that the duct tape was “not only equal to but [exceeded] the efficacy of cryotherapy,” which worked in 60 percent of the cases. But 85 percent of the duct tape patients were cured—significantly more effective than cryotherapy for treatment of the common wart. More effective, and fewer side effects. “The only adverse effect observed in the duct tape group during our study was a [small] minimal amount of local irritation and [redness]”—whereas cryotherapy hurts.

Oh, you want to hear the saddest thing? “1 young child actually vomited in fear of pain before each [cryotherapy session.]” They were like torturing the poor kid.

Cryotherapy can cause pain, and bloody blisters that can get infected, and mess up your nail bed.

So, duct tape: more effective, fewer side effects, and more convenient. Compare applying a little duct tape at home to making multiple clinic visits, dragging the poor kid back every two weeks. I mean it’s like a win-win-win.

Duct tape can now be “offered as a nonthreatening, painless, and inexpensive technique for the treatment of warts in children.” I mean, how much does a little piece of duct tape cost? So, it’s like a win-win-win-win. Ah, but the money you save is the money the doctor loses. There’s no way the medical profession is going to just let this go unchallenged. Further studies were performed, and failed to show an effect, and so we end up in the medical literature with conclusions like this: “Is duct tape effective for treating warts?” “Bottom line? No.”

Huh. Is duct tape really not effective after all, or was there some kind of critical design flaw in the follow-up studies? We’ll find out, next.

One of the “unusual, innovative, and long-forgotten remedies” noted in this dermatology journal  was “the use of duct tape” to cure warts—finally put to the test. There’s all sorts of conventional therapies, from acid to cryosurgery to lasers, but most of these are expensive, or painful, or both. Whereas the simple application of duct tape is neither—and may even be “more effective” than trying to freeze the warts off.

Some doctors lauded the study, noting they had been using duct tape for decades as a painless yet effective treatment, as opposed to surgery and other destructive therapies. The only downside being your patients may think you’re off your rocker, but hey, when it works, they appreciate your wise choice to minimize discomfort.

Other doctors were not so amused. Here they are spending money on all this fancy equipment and then along comes duct tape? Studies like that “could damage the reputation of cryosurgery,” complaining that the 10-second application of liquid nitrogen they used in the study was too short, so it was an unfair comparison. And evidently you really have to get in there and freeze until you get a blistering reaction. And yes, it hurts but too bad, even making light of the poor child who vomited out of fear of the pain prior to each freezing by making some joke about it.

Did they have a point, though, about the 10 seconds? Well, in the duct tape versus cryotherapy trial, those 10-second cryotherapy treatments worked 60 percent of the time, which is actually better than the results of most cryotherapy studies that only seemed to cure about 50 percent. In fact, the typical cryotherapy for warts works so poorly that statistically it didn’t even beat out placebo. So, all that pain may be for nothing, though aggressive cryotherapy does seem to work better.

See, what they should have done, wrote another doctor in response to the duct tape trial, is take a scalpel to it, and then really blister it up, and then you go back a week later and try to cut and crater it out, and then maybe go back a third time, bragging that they can get closer to a 90 percent cure rate. Yeah, but at what cost?

In the duct tape trial, one patient “lost his study wart in a trampoline toe-amputation accident.” Hey, there’s a treatment that’s 100 percent effective—amputation! But, at what cost? Eighty-five percent of the duct tape patients were cured with no pain or tissue damage, whereas aggressive cryotherapy may require lidocaine injection nerve blocks to “take the cry out of cryotherapy,” and can cause permanent tissue damage. You can end up with the big necrotic frostbite lesions. I mean, in one sense, tissue damage is the whole point of freezing warts, but you can end up causing these deep burns or end up rupturing tendons, which can cause permanent disability, or cause extensive scarring in rare cases. Just the “psychological stress” of having to keep going back for this painful procedure may ironically impair our ability to fight off the wart viruses in the first place.

And so, “even if the effectiveness of duct tape…is shown to be merely equivalent to that of cryotherapy,” it would be better; and it was shown to be even more effective, in fact maybe most effective. Compared to 10 other wart treatments, duct tape beat out them all in terms of effectiveness, and also in terms of cost—cheaper than all but the DN option (which stands for “do nothing.”) Compared to the most cost-effective prescription treatments available, OTC duct tape, meaning over-the-counter duct tape, is 10 times cheaper. “It is an unusual and welcome event in health care when a common ailment is proven equally amenable to an inexpensive, tolerable, and safe alternative therapy.”

But wait. If you look at the latest Cochrane review, which is like the gold-standard of evidence-based reviews, they acknowledge that cryotherapy is less convenient, more painful, more expensive. But, while in the earlier review they did get excited about the effectiveness of duct tape, in two subsequent studies, duct tape seemed to totally flop. So, should we give up on duct tape for warts, or is there another side of the story? We’ll find out in the thrilling conclusion, next.

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Image credit: Maximilian via Adobe Stock Photos. Image has been modified.

Motion graphics by Avocado Video