How Botox Smooths Wrinkles and Slims the Face: 4 Effects

If you are unfamiliar with aesthetic medicine, you may not know what AestheFill, picosecond lasers, or HydraFacial can do. But even so, you have very likely heard of Botox and know roughly what it does: after injection the face can look smaller and the skin tighter. Do you really know the secret behind skin looking younger, though?

Botox, as everyone calls it, has the full name botulinum toxin and is one of the most toxic neurotoxins on Earth. Its main action is blocking nerve-muscle signals, and in severe cases it can cause muscle paralysis, respiratory failure, and even endanger life.

Don't worry yet. At very small doses and applied in the right places, it can smooth wrinkles and fight aging! The principle is to paralyze the underlying muscle to treat overactive muscles. Once the muscles relax, fine lines and wrinkles on the face improve, leaving the skin smoother and younger.

Botulinum toxin comes in 8 types, Type A to H. In medical use, there are mainly two, Type A and Type B, and Type A is the most widely used. The 4 major Botox brands on the market, BOTOX, Dysport, Xeomin, and Letybo, are all Type A botulinum toxin. (Read more: 4 Major Botox Brands Compared! Suitable Areas, Prices, Pros and Cons Revealed)

Where is Botox used, and where does it work best?

Botox effect 1: Smoothing wrinkles

Botox is the most commonly used treatment in aesthetic medicine for softening all kinds of wrinkles, and a single injection session produces visible change. The areas most often treated are frown lines, forehead lines, and crow's feet. Other treatable areas include fine lines under the eyes, bunny lines on the nose, lower-eyelid bulges (aegyo-sal), wide nostrils, and a slack jawline.

Botox effect 2: Relaxing facial contours

Frequent gum chewing and teeth grinding at night are causes of masseter hypertrophy, which can lead to a square face. Botox helps relax the jawline, correct facial asymmetry between the two sides, and even relieve teeth grinding.

Botox effect 3: Improving hyperhidrosis

People with active sweat glands or underarm odor no longer need surgery to remove sweat glands or microwave treatment. Botox injections alone can solve excessive sweating.

Botox effect 4: Contouring the legs

Some women are very bothered by thick calf muscles, but you read that right: Botox can improve even "radish legs." Botulinum toxin relaxes the calf muscles and smooths the muscle lines of the legs.

How long does Botox last?

When Botox is injected, a very fine needle places a measured dose of botulinum toxin precisely into the treatment area. The physician decides the dose and number of injection points based on the wrinkles. It feels a bit like a mosquito bite, with low pain. Injection takes about 5 to 10 minutes, and you can return to normal activities right after treatment. Wrinkle improvement is seen within about 3 days, and the effect is most obvious within 2 weeks.

How long Botox lasts varies with individual constitution; on average it lasts 4 to 6 months. Over time, the effect gradually fades and wrinkles slowly return. To keep the effect going, you need regular injections 2 to 3 times a year, and you can add injection areas at will in between.

Notably, botulinum toxin only acts on the area injected and does not affect the movement of other muscles, so expressions still look natural after treatment. However, you may notice that some celebrities look stiff after Botox, with a smile that does not reach the eyes. That means the dose was not well controlled.

How many units are enough for a clear Botox effect?

Botox is actually measured in units, not in the more familiar cc or ml, but in "U." Generally, a wrinkle area on the face takes about 8-16 U, slimming the face or improving masseter hypertrophy about 32-50 U, calves usually more than 200 U, and hyperhidrosis about 50-100 U per area.

The exact dose depends on each person's situation, and the physician will assess it based on the wrinkles. Dose and effect are related, though: with a low dose the effect will certainly be shorter, and you will need to return more often for additional injections.

How is Botox priced?

Botulinum toxin is priced per unit (U). The average price per U for the 4 major brands ranges from NT$100 to NT$225. To learn the differences between brands in detail, see the article 4 Major Botox Brands Compared! Pros, Cons, Prices, and Results at a Glance.

However, if you are treating more areas, buying a whole vial of botulinum toxin at once is more cost-effective and helps achieve a better Botox effect.