Choosing from the selection of high-tech skin-care devices on the market, from LED masks to ultrasonic spatulas, can be downright overwhelming. But if you've spent any time at all researching what's out there, chances are you've heard of microcurrent devices.

These tools are designed to stimulate your facial muscles to create a more lifted look, and are often likened to a "workout for your face." Taylor Worden, a celebrity esthetician and founder of Taylor Worden Skin, goes so far as to refer to the devices as "non-surgical facelift machines." You may already be familiar with popular at-home microcurrent tools, such as NuFace devices and the Foreo Bear.

The catch: At-home microcurrent devices cost a pretty penny, ringing in at anywhere from $150 to nearly $400. Before you drop a lot of cash on one of the beauty tools, learn everything you need to know about microcurrent devices, including how they work, their benefits, and how to use them for optimal results.

"Microcurrent devices use low-voltage electricity to give your facial muscles a workout," says Azadeh Shirazi, M.D., a board-certified dermatologist. "They deliver little shocks to the muscle, [which] helps tone the muscle and boosts cellular activity."

Think of using these devices as lifting weights, but for your face, says Worden. At-home devices are a DIY alternative to professional microcurrent facials, which are typically carried out with machines that utilize higher-voltage electricity for more pronounced results. "An in-office treatment is like a two-hour session with a personal trainer, at-home devices are like walking for ten minutes on a treadmill," says Dr. Shirazi. You can achieve results — albeit subtler changes — by using the at-home devices with consistent use, says Rachel Nazarian M.D., board-certified dermatologist at Schweiger Dermatology Group.

Microcurrent therapy helps strengthen facial muscles by increasing the production of ATP, explains Dr. Shirazi. If it's been a minute since your last science class, ATP is your cells' energy source, which your body can use to carry out various functions including muscle contraction. The gentle electricity emitted from microcurrent devices triggers an increase in ATP production, which allows for muscle contraction that strengthens facial muscles over time, according to a study in Clinical Orthopaedics and Related Research. (Related: Are Jade Rollers Really a Magical Anti-Aging Skin-Care Tool?)

As you get older, the muscles in your face begin to atrophy causing the appearance of loose skin, Emma Goodman, an esthetician, previously told Shape. The natural decrease in muscle strength with age can contribute to signs of aging in various regions of your face, such as your chin and eyelid areas. The hope with microcurrent therapy is to strengthen those muscles, encouraging a more lifted appearance, explained Goodman.

Additionally, microcurrent may help stimulate collagen production, since ATP is also used for collagen production. Collagen is a protein in your skin that helps give it structure, contributing to a plump, firm complexion. (Related: These Botox Alternatives Are Almost As Good As the Real Thing)

Few clinical trials have examined the side effects of microcurrent therapy, but dermatologists generally consider it safe for those who don't have any contraindications (reasons that someone should avoid a given treatment), says Dr. Nazarian.

Contraindications for microcurrent therapy include having a cardiac pacemaker or metal implants, according to Hadley King M.D., a board-certified dermatologist in New York City. The currents that a microcurrent device emits may interfere with functionality of pacemakers or cause heating of the metal implants. "It's best to talk to your doctor if you have epilepsy, heart conditions, a pacemaker, metal plates or pins, or if you are pregnant as there may be risks and contraindications for microcurrent treatment," adds Dr. Shirazi. You also shouldn't use microcurrent therapy if you've just been injected with any neurotoxins, such as Botox, which have the opposite effect of relaxing your muscles, says Worden. "You should wait at least two weeks to do microcurrent if you have had Botox," she says.  

If you decide to invest in a microcurrent device, it's important to follow its accompanying directions closely, says Worden. As a rule of thumb, though, "you want to use it three times a week for five to ten minutes," she says. Some brands, such as NuFace, advise using a device for five days a week for the first 60 days, then dropping down to three days a week. Dermatologists stress that consistency is important if you want to achieve results from these at-home devices.

For most devices, you'll need some type of conductive gel or serum to help the current reach the muscles and help the device glide on your skin without major stinging. Typically, brands that sell microcurrent devices also offer a suitable gel. If you're looking for a more inexpensive option, though, you can try aloe vera gel mixed with salt. Aloe vera is 99 percent water and when water is paired with salt it creates a conductive path for electricity.

Make sure you're starting with a clean face before applying any gel and using the device to avoid spreading bacteria. "Place the device on the skin, making sure to apply a slight pressure to assure full contact between the electrodes and the skin," says Dr. King. "Move the device using a very slow linear motion along the jawline." You'll want to use similar motions when using a microcurrent device on other areas of your face, such as your cheekbones and forehead. (Devices typically come with detailed instructions on how to use them.) Once you're done with the treatment, remove the gel — unless it's a designated leave-on treatment — and you can follow up with your skin-care routine. (Related: What a Proactive Anti-Aging Skin-Care Routine Looks Like)

You should watch out for any irritation from the gliding or rubbing of the device, which can worsen some skin conditions, such as acne, if you aren't using the tool correctly, says Dr. Shirazi. Brief tingling and facial twitching can also occur as a result of the voltage, says Worden.

Plan on rinsing your microcurrent device after each use and giving it a more thorough clean at least once a week. "Dirt, oils, bacteria, and yeast can all be found on dirty massagers, and therefore lead to breakouts," says Dr. King. Place a few drops of antibacterial dish soap to scrub the device or a cleansing wipe to ensure you're not exacerbating skin concerns, such as acne.

"Ideally, [a microcurrent device] would be used as a part of an anti-aging regimen, [but] more for preservation than actual repair, given its subtle results and need for consistent use," explains Dr. Nazarian. In other words, it's important to manage your expectations when it comes to using your at-home microcurrent device. Microcurrent therapy is more for prevention and modest rejuvenation as opposed to actually reversing existing anti-aging concerns, says Dr. King.

Ultimately, the devices have some enticing potential benefits, provided you commit to using them regularly. If your skin-care goals include a more lifted and sculpted face, then you might find that a microcurrent device is a worthy addition to your routine.