Botulax by Hugel: Korean Botulinum Toxin Type A

Korea’s Number One Neurotoxin, Now Known Globally as Letybo

Botulax is a botulinum toxin type A product developed by Hugel Inc., a South Korean biopharmaceutical company founded in 2001 and headquartered in Chuncheon, South Korea. Since its domestic launch, Botulax has held the position of Korea’s top-selling botulinum toxin and has been distributed to more than 70 countries worldwide.

In the United States, Botulax is marketed under the name Letybo, having received FDA approval in 2023, making Hugel the only South Korean company with regulatory approvals in the world’s three largest botulinum toxin markets: the U.S., China, and Europe. A dedicated page on this site covers Letybo in more detail as an FDA-approved neurotoxin available in the U.S.

What Botulax Is

Botulax is a type A botulinum toxin formulation containing clostridium botulinum toxin type A, human serum albumin, and sodium chloride. It is produced as a freeze-dried powder and reconstituted with saline before injection.

It works by temporarily blocking the release of acetylcholine at the neuromuscular junction, preventing muscle contraction in the treated area. This relaxation of the targeted muscle smooths dynamic wrinkles and expression lines caused by repetitive facial movement.

How Botulax Compares to Other Toxins

Botulax contains 844 units of neurotoxin protein per 100U vial, which is higher than some competing Korean formulations. Studies have shown that Botulax demonstrates greater potency per unit compared to Botox in some in vitro and in vivo measurements, which can be a relevant consideration for practitioners dosing larger muscle groups.

Its relatively high molecular weight and moderate albumin concentration limit its spread into surrounding tissue, which makes it useful for larger treatment areas such as the masseter and calf muscles, where precise, contained relaxation is desired.

Results typically begin to appear within 3 days of injection and reach full effect by day 14. Duration of effect is generally 3 to 6 months, consistent with other botulinum toxin type A products.

Common Aesthetic Applications

Botulax is used across a wide range of cosmetic indications in Korean dermatology practice, including glabellar lines (frown lines), forehead lines, crow’s feet, perioral wrinkles, neck bands, and hyperhidrosis (excessive sweating). It is also widely used in Korea for masseter reduction (jaw slimming) and calf slimming, both of which are more commonly requested procedures in Korean aesthetic practice than in Western markets.

Safety and Regulatory Status

Botulax has undergone extensive clinical study and holds approvals from the Korean Ministry of Food and Drug Safety (MFDS), the U.S. FDA (as Letybo), and regulatory bodies across Europe and China. When administered by a trained and licensed provider, Botulax has a well-established safety profile consistent with other botulinum toxin type A products.

As with all botulinum toxin products, Botulax should only be administered by a qualified medical professional. It is a prescription product, and its use requires thorough patient evaluation, proper technique, and knowledge of facial anatomy to achieve safe and effective results.