The idea was first devised in 1984. Before then, nobody had thought to deliver the very drug people were addicted to straight through their skin, albeit in tinier doses than their brains had been accustomed. But transdermal nicotine patches were a hit. And today, behind going cold turkey, they have remained one of the most popular and effective ways to kick the habit.

The same science that introduced nicotine replacement therapy through the skin is now being applied to nearly every disease and condition out there — just in the opposite direction. Instead of nicotine doses shrinking with time, emerging technologies that target pediatric food allergies gradually increase the patient’s level of allergen exposure. Elsewhere, researchers are developing patches that rely on microneedles to deliver medication syringe-free and fitness trackers that communicate with computers and smartphones.

Training The Body

Allergies are a curious beast. When the body encounters an antigen it doesn't like, it treats the otherwise harmless substance as a perceived threat. So, your immune system goes haywire. Normal things like peanut proteins, pollen, and dust shouldn't arouse any extreme response. And skin-based immunotherapy, known as epicutaneous immunotherapy, exploits the body's natural predisposition to develop a tolerance. When it comes across these allergens, a special type of immune cells called T-cells swoop in to quiet the immune response. That immune cell reaction doesn't always happen when immunotherapies are administered orally, where the allergen can disperse to other areas of the body.

The Viaskin Peanut patch is the latest advancement. It hails from DBV Technologies, a French biotech company and seeks to replace existing oral immunotherapy options. “The skin-based approach has a major theoretical and now apparent actual advantage over oral immunotherapy in its safety,” Dr. Frank Lobo, a clinical instructor in pediatrics at the Yale School of Medicine, told Medical Daily.

Oral immunotherapy works by the same principles as nicotine patches, but through food-based methods that get absorbed into the body from underneath the tongue. While sometimes effective at reducing a child’s sensitivity to the key peanut protein that triggers the allergy, side effects can range from itchy mouths to swollen stomachs. “Some children undergoing oral immunotherapy do indeed suffer reactions to the oral exposure,” said Lobo, who was not involved with the research. On the other hand, “skin exposure to a very defined, small quantity of peanut allergen limits the risk for systemic exposure, both in theory and, it appears, in real-life practice.”

Lobo is referring to a recent study presented at the annual meeting of the American Academy of Allergy, Asthma and Immunology. The study found that among 221 people with severe peanut allergies, ages 6 to 55, the Viaskin patch allowed half the participants to tolerate 1 gram of peanut protein, or about four peanuts, after one year, which was more than 10 times their previous threshold of exposure.

“This is indeed happy news and very promising, not only for peanut allergic children, but for all with food allergy,” Lobo said. DBV Technologies, for instance, is also at work on a Viaskin Milk patch for kids with an allergy to cow’s milk protein, generally the first allergy kids will develop. Given the mode of transmission, Lobo added, “in theory, any food allergen — egg, milk, tree nuts, seafood, for example — could be placed in the skin patch. It is a very important development for all who suffer with food allergy.”

No More Needles?

Patches aren’t limited to peanut allergies. They also serve a practical benefit as an alternative to normal-sized needles. Diabetics, for example, may see breakthroughs in how they check blood glucose levels, if engineers from UC San Diego can win approval for their temporary tattoo design. Or consider the five-minute painkiller delivery method of a microneedle patch. Scientists at the University of Singapore have crafted a stick-on device that, while resembling a cute bird, carries dozens of 600-micrometer-long needles that shoot lidocaine into the patient’s system.

Then there is the potential to just get healthier. Last year, Northwestern University and University of Illinois engineers unveiled their thin, fluid-filled envelopes that sit on the skin similar to the blood-glucose monitors from UC San Diego. Inside the envelope are sensors that can pick up heart rate and certain brain activity, and transmitters that can send the signal to a smartphone app or computer, where the data can be analyzed. The best part, the team says, is that unlike other fitness trackers, which tend to be bulky and a hassle, theirs is forgettable.

Peanut allergies are becoming more common by the year. Experts point to an increasingly sterile society that rids itself of germs before young immune systems can learn to fight them. Then, when the foreign invader of an allergen emerges, the body is defenseless. Skin-based options may be science’s way of reclaiming some of that lost power.

After more than 30 years on top, the nicotine patch may be forced to concede to a young up-and-comer. Recent data suggest replacement therapy options like patches and gum are falling in prominence as e-cigarettes take over the tobacco landscape. But in their wake are a host of other offshoots that make use of the same technology that let transdermal patches first rise.