What Is Letybo? Experts Break Down Korea’s #1 Neuromodulator

Making a trip to Korea is on every beauty lover’s bucket list. The thought of filling an entire suitcase with K-Beauty products you’ve never seen before or making a coveted aesthetic treatment appointment you can’t get anywhere else in the world is enough to make that impulsive plane ticket purchase. But now there’s one treatment that has finally made its way Stateside to appease those hungry for an advanced K-beauty skin treatment closer to home: Letybo.

Letybo, more formally known as letibotulinumtoxinA or Botulax and colloquially known as “K-Tox” in Korea, is a botulinum toxin type A neuromodulator. It is specifically FDA-approved to treat the glabellar lines (aka the frown lines between the brows) in the US, but works pretty much the same as other neuromodulators such as Botox, Dysport, Xeomin, Jeuveau, and Daxxify to soften dynamic lines on your face. What sets it apart from the rest, Y. Claire Chang, MD, board-certified cosmetic dermatologist at UnionDerm, says, is its softer, faster, cheaper, and more natural-looking results. “It has a long history of use in Korea with a highly regarded manufacturer, Hugel Inc. Its pricing in Korea is more competitive than other international brands, making it a more affordable and widely available alternative,” says Dr. Chang.

Since its debut in the US in March 2025, Letybo has been positioned as Botox’s biggest competitor in the injection space. And with 31 million treatments globally and approval in 65 other countries, including Canada, Australia, and many European countries, Letybo only reinforced K-Beauty’s dominant presence in Western beauty markets.

“K-beauty, and its more advanced K-Aesthetics, has shown it’s here to stay in the US,” says Ethan Min, chief executive officer of BENEV, the American drug manufacturer that partnered with Hugel Inc. to bring Letybo to the States. “The adapted philosophies, such as high levels of innovation, youthful appearance, a skin-first approach, and the pursuit of skin quality, have proven to be equally as appealing to US consumers as those in Korea.”

How does Letybo work?

To soften dynamic lines, Letybo reduces muscle contraction. It blocks the release of acetylcholine, which is what our body uses to move our facial muscles. When a neuromodulator blocks the acetylcholine release, Dr. Chang says that’s how it softens facial expression lines like frown lines, forehead lines, crow’s feet, and bunny lines. Right now, it is only FDA-approved for the frown lines between the brows, but she says it can be used off-label in other areas.

The Downsides

Whether it’s Letybo or Botox, Sonia Badreshia, MD, board-certified dermatologist at
Elite MD, says that any botulinum toxin has the same side effects: risk of bruising, headache, rare hypersensitivity, swelling, or eyelid ptosis. She advises that those who are pregnant or breastfeeding should avoid getting any neuromodulator injection, as there is limited data available about its safety in those instances. Dr. Chang adds that those with active infections, wounds, or rashes in the desired treatment area should wait until the skin is fully healed.