Body Contouring

TrapTox: Shoulder Contouring with Trapezius Botox Injections

13 November 2023

Trap Tox is now regaining popularity as “Barbie Botox” on TikTok thanks to the aesthetics of Barbie’s body proportions.


Botox or botulinum toxin is best known for its wrinkle removal effects but did you know that it can also be used for body contouring? Besides slimming the jaw and calf muscles, shoulder botox injections or trapezius muscle botox is used to slim and sharpen bulky shoulder muscles- that’s called #TrapTox or Barbie Botox on TikTok. The result of trapezius botox or shoulder botox injections is reduced neck and shoulder tension and a slimmer and more feminine silhouette for females ala Barbie.


Related blogposts:

More Than Wrinkles: 5 Surprising Uses for Botox


The trapezius muscle is a large muscle that extends from the back of the head and neck to the shoulders. When the trapezius muscle is enlarged or hypertrophic, the shoulders look bulky and more masculine. Hypertrophic trapezius muscles also have the effect of making the neck look shorter and face wider.


One way to treat hypertrophic trapezius is with Botox/ botulinum toxin injections. Barbie Botox Trapezius botox injections help to correct and contour big shoulder and collarbone muscles for a slimmer silhouette. Trapezius botox or shoulder botox injections started getting popular 4-5 years ago in South Korea and China. In Singapore, I’m noticing an increasing interest in botox injections for slim arms/ shoulders. This review will examine contouring of the shoulder and collarbone muscles with Barbie Botox/ trapezius botox injections and safety issues surrounding this treatment.


Overactive or enlarged trapezius muscles can make the neck look short and the face wider, on top of making females look more masculine


What does TrapTox/ trapezius botox treat?

The trapezius muscle is a large flat muscle that extends from the back of the head and neck to the shoulders sideways. The function of the trapezius muscle is to pull the shoulders upwards (shrugging) and backwards and neck extension and turning.


Enlarged trapezius muscles can occur in people who have overactive trapezius muscles. Overactive trapezius muscles can become hypertrophic. The enlarged trapezius muscles makes the shoulder and muscles above the collarbone look bigger. The neck also looks shorter and the face looks wider in comparison. The overall appearance is more masculine and stockier. For females, this masculine appearance can be obvious, especially when shoulder-baring outfits are worn.


Overactive trapezius muscles can occur in non-body builders. In a condition known as upper crossed syndrome, poor posture strains the trapezius muscle, causing pain, stiffness and aches in the upper back and neck.


Upper cross syndrome is seen in people who bend their backs and necks forward, similar to a hunched posture or slouching. This posture is also commonly seen in people who hunch their backs and neck while working at their desks. The constant overactivity of the muscles causes the trapezius to become overdeveloped. So while you’re reading this blogpost- remember to stretch!


Trapezius botox injections are one way of treating overactive or overdeveloped or hypertrophic trapezius muscles. Botulinum toxin is injected into the trigger points of the muscles to relax the trapezius muscles. The trapezius muscle slims down over weeks and the shoulders and collarbones look slimmer and more feminine.


Image credit: Jeong et al.



How does Trap Tox/ trapezius botox work?

Botox or botulinum toxin is a neurotoxin that relaxes muscles. Botulinum toxins acts at neuromuscular junctions to relax muscle. When used in the face, botox relaxes the facial muscles to remove wrinkles. When injected into the masseter muscles, botox relaxes the jaw muscles to reduce teeth grinding and slim down the face shape.


Similarly, when botulinum toxin is injected safely into the trapezius muscles, the muscles can be relaxed without affecting normal movement of the arm, shoulder joint, back and neck. As the overactivity of the trapezius muscle is curbed, the hypertrophic trapezius muscles lose their bulk and size. This is akin to a bodybuilder who stops working out and loses his muscle mass over weeks.


Over a few weeks, the bulky hypertrophic muscles slim down for a slimmer and more elegant neckline. The results of trapezius botox lasts for 4-6 months.


How is Trap tox/trapezius botox for shoulder contouring done in Singapore?


Botulinum toxin is injected into the upper shoulder (trapezius muscle) directly. These injections are placed at the points of the nerve that supplies the trapezius muscle. 4-5 injections points are required on average. The entire treatment will take approximately 5-10 minutes.


Are TrapTox/ trapezius botox injections safe? What are the side effects of shoulder contouring with botulinum toxin?


Botulinum toxin has been used for medical treatments for decades in various specialities including neurology and dermatology. The safety issues surrounding Botulinum toxin have been discussed in this blogpost Is Botox Deadly?


The use of botulinum toxin for shoulder contouring is an off-label indication. There are a few studies on Barbie Botox or  trapezius botox injections for pain and contouring. These studies show that trapezius botox injections are generally safe and side effects that occur are temporary. If you’d like to read more about interesting uses for Botox, this review More Than Wrinkles: 5 Surprising Uses for Botox will share about the off-label uses for Botulinum toxin in dermatology.


The dosages of Botulinum toxin used for Barbie botox or trapezius muscle injections is relatively small. With any injections, there may be muscle aches and soreness related to the injections rather than botulinum toxin. Some of the specific risks related to botox trapezius injections are neck and shoulder weaknesses and imbalances in sizes of both shoulders.


Update June 2023: I also share more about TrapTox in New York Post. Link here to the full article.

What are the alternatives to Barbie Botox/ TrapTox/ trapezius botox injections for shoulder contouring?


The alternative to Barbie botox or trapezius botox injections to slim down large shoulder muscles is surgery. (e.g. skeletonisation and defatting of the large muscles and tissues). The advantage of surgery is that the results are longer lasting than trapezius botox. One disadvantage of surgery for shoulder contouring is that the shoulders look hollowed out and the neck- shoulder contours look unnatural.


How long do the results of Trap Tox/ trapezius botox for shoulder contouring last?

The results of botulinum toxin injections last 4-6 months.

How soon can the results of Trap Tox/trapezius botox for shoulder contouring be seen?

It takes approximately 4-6 weeks for the shoulder muscles to slim down after trapezius botox injections.


How many units of Botox are required for #TrapTox/ trapezius botox injections for shoulder contouring?

40-50 units of Botox are used for trapezius botox for shoulder contouring on each side.


Am I suitable for shoulder conoturing? What are the pitfalls or limitations of trapezius botox injections?

Trapezius botox injections for shoulder contouring are effective for overactive or hypertrophic shoulder muscles. If your shoulders are enlarged due to other reasons, trapezius botox injections may not be effective in slimming down the shoulders.


If you have previous injuries or surgeries to your shoulder, arms, necks- please inform your doctor. You may not be suitable for botox injections to the shoulders.


 South Korean actress Suzy Bae’s slender shoulder and long neckline.


Conclusion on TrapTox/ trapezius botox injections for shoulder contouring

One of the newest trends in Singapore is shoulder contouring with trapezius botox injections- and now #TrapTox on TikTok! Botulinum toxin slim down overactive and large shoulder muscles for a slimmer and more elegant neck and shoulder line. Trapezius botox injections is also one of the treatments for aches and pains due to overactive trapezius muscles.


One common cause for overactive and hyperactive trapezius muscles is poor posture. Hunching while at our desks for prolonged period strains the back and neck muscles, causing the Upper Crossed Syndrome.


The use of botulinum toxin for shoulder contouring is an off-label indication. Small studies have shown that trapezius botox injections for shoulder contouring is safe- caveat here is to see a doctor experienced with using Botulinum toxin. The side effects of trapezius botox injections are namely muscles; rarer complications include weakness of shoulder and neck muscles; and imbalances in shoulder appearance. The side effects and complications of shoulder contouring with botulinum toxin are temporary and last for weeks.


If you enjoyed this blogpost, you might also like the following blogposts on botulinum toxin:

More Than Wrinkles: 5 Surprising Uses for Botox

Shoulder Contouring with Trapezius Botox Injections

Is Botox Deadly? 5 Things You Need to Know About Botox Safety

Baby Botox and Preventive Botox in Your 20’s is Real

A Guide to A Slimmer V Face: Jaw Botox and Chin Filler Review

Bruxism: Symptoms, Causes and Treatments for Teeth Grinding

Botox vs Fillers: the Differences

NoTox: Non-Invasive Botox Alternatives




Get in touch with me by completing the form