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

21 October 2022

Over the last few days I’ve received a number of enquiries regarding the safety of Botox/Botulinum toxin in response to the unfortunate news of a young female patient that passed away in an licensed medical clinic in Singapore, presumably after a Botox injection – Police Probing Case After Woman Dies Following Botox Treatment in Clinic. The actual medical or aesthetic procedure that she underwent and the events that transpired still remain unknown as the details have not been released. However, news outlets in Singapore have reported that this young lady underwent Botox injections prior to her death.


Update October 2022:

This case has been read in court recently; and the victim’s cause of death has been determined to be due to EDTA toxicity, and not related to botulinum toxin. EDTA or ethylenediaminetetraacetic acid is used in chelation therapy in cases of poisoning. In this victim’s case, there was no indication for EDTA therapy. Reports from Straits Times and CNA here.


I have written this post with the intention of highlighting and sharing some of the pertinent issues and FAQ surrounding the safety of  botulinum toxin. I feel that it is better to objectively discuss the safety issues and controversies surrounding botulinum toxin rather than to let these assumptions take a life of their own or dismiss a very useful drug (botulinum toxin) that has been used in various medical specialties including neurology and dermatology.


Death due to injection of botulinum toxin from an aesthetic treatment is highly unlikely in my opinion. I will also be sharing with you the reasons why I disagree that it was botulinum toxin that led to her death. Until the post mortem results and investigations are complete, speculations about the cause of death would create unnecessary fear. This incident in Singapore also brings to mind of another widely publicised incident in Hong Kong in November 2018, where another death occured in a plastic surgeon’s clinic after what was reported to be a botulinum injections that the patient underwent- Hong Kong Plastic Surgeon Arrested for Female Banker’s Suspected Botox Death. It is unclear if Botox injections led to this lady’s death as the investigations and post mortem reports did not yield anything conclusive.


That said, it is understandable that most of you are very worried and concerned about the safety of Botox/ botulinum toxin injections. Botulinum toxin injections is one of the most commonly requested treatments in Singapore, especially for treatment of wrinkles and jaw slimming/ bruxism.


Related blogpost:

Bruxism: Causes, Symptoms and Treatments for Teeth Grinding


1. What is Botox? Is Botox the same as botulinum toxin?


Although used almost interchangeably in the media, Botox and botulinum toxin are slightly different. Botox is one of the brands of a of neurotoxin called Botulinum toxin A. This neurotoxin is derived from a bacteria called Clostridium Botulinum.


Our nerves send signals to our muscles to cause the muscles to contract i.e. move. These signals occur specifically at nerve endings next to the muscles and these nerve endings are called neuromuscular junctions. Botulinum toxin binds to these neuromuscular junctions to interfere with the signal transduction between the nerve endings and the muscles. This prohibits the muscles from contracting or moving and relaxes muscles.


What is botulinum toxin used for? Botulinum toxin is used to treat patients in conditions where the muscles are overactive or hyperactive i.e. the muscles are moving too much or too forcefully. We are familiar with Botulinum toxin for treating wrinkles, jaw slimming or bruxism, hyperhidrosis (excessive sweating)  and calf slimming. However, did you know that Botulinum toxin has been used in specialties such as neurology and urology to treat conditions such as migraine, overactive bladder, upper and lower limb spasticity?


When injected into facial muscles like the jaw muscles (masseter muscles), the muscles relax and eventually slim down. This is why botulinum toxin is used to treat bruxism and for jaw slimming to achieve a slimmer, sharper, V shaped face in most Asian countries like Singapore. Likewise, when botulinum toxin is injected in the facial muscles, say the forehead muscles which cause the horizontal creases when we frown; the forehead wrinkles improve.


Related post: A Guide to a Slimmer V Face: Jaw Reduction Botox and Chin Filler Review



Botulinum toxin is an effective treatment for wrinkles. Sharing with you my before after pictures of Botox injections for my crows’ feet wrinkles at the outer corners of my eyes. How long does it take for Botox to kick in? On the left you can see my crows’ feet wrinkles in their full unadulterated glory. On the right is the result 1 week after I injected Botulinum toxin into my wrinkles (by myself of course, perks of being an aesthetic doctor). Botulinum toxin is a very useful drug and can give natural looking results when done right.


Clearing the confusion: Botox vs Botulinum toxin


Botox is one of the brands of botulinum toxin that is US FDA approved and approved by Health Science Authority (HSA) in Singapore for use.


At present, there are commercial formulations of botulinum toxin A that are approved by both the US FDA and Singapore’ HSA for treating dermatological conditions: Botox (onabotulinum toxin A), Dysport (abobotulinum toxin A) and Xeomin (incobotulinum toxin A).


Very recently this year, the US FDA has approved another brand of botulinum toxin called Jeuvea for treating facial wrinkles. However, please note that Jeuveau has not  received Singapore’s HSA approval for use in Singapore.


Botox was the first type of botulinum toxin A to receive US FDA approval for treating glabellar wrinkles in 2002, followed by Dysport to receive US FDA approval in 2009 and Xeomin to receive US FDA approval in 2010. Not surprisingly, Botox enjoys the market dominance of brands of botulinum toxin used for aesthetic dermatologic treatments and this is why the brand, Botox is synonymous with botulinum toxin.


Update November 2021: Botox and the Covid vaccine.


Is it safe to get Botox or dermal fillers if you’re getting the Covid-19 vaccine?

This concern arose because of reports of facial swelling in patients who had facial fillers  after receiving the Covid vaccine from Moderna. There has been no reports of side effects or adverse events in patients who received Botox injections after getting the vaccine. Botox is a neurotoxin with very localised effects; and Botulinu toxin gradually gets broken down in the muscle. The likelihood of developing facial swelling after getting Botox and the Covid vaccine is very rare. Nonetheless, if you would like to err on the side of caution, you can take a 2 week gap between your Botox injections and Covid vaccines. You can read more in Covid-19 Vaccine and Facial Swelling After Dermal Fillers.


2. If botulinum toxin is a neurotoxin, are botox injections safe?


Botulinum toxin for commercial use is produced under very strict conditions with multiple steps to ensure the safety of patients and efficacy of treatments. The preparation of Botulinum toxin undergoes multiple steps of extraction and purification before it is eventually crystallised and packaged as the final product that we know it to be- Botox.


Since news of this death supposedly related to Botox went viral in Singapore; a good number of my patients have asked me whether botulinum toxins injections for aesthetic treatments can cause cardiorespiratory failure and death, as suggested by local media outlets. The answer is: Highly unlikely; and let’s look at why so.


Not quite a deadly complication of Botox; but a parody of too much Botox and fillers with prosthetics by Canadian pop star, The Weeknd.


3. Can Botox/botulinum toxin cause cardiorespiratory failure or death?


As I have explained above, botulinum toxin has to be injected into the muscles to. So, assuming that  a patient who underwent botox injections to suffer from cardiorespiratory failure; two conditions have to be fulfilled:


1. The botulinum toxin injected has travel from the muscles to the heart and lungs and;

2. The dosage of botulinum toxin injected to be lethal enough to cause the heart and lungs to failure.


Let’s examine these two conditions.


1. Diffusion of botulinum toxin reaching the heart and lung muscles from the muscles

So far, data suggests that Botulinum toxin has a very localised mode of action. This means that when correctly injected into the intended muscle, Botulinum toxin has a very precise mode of action. If you were to receive Botulinum toxin injections to your jaw muscles, your jaw muscles will relax and slim down; but do not expect your forehead or crows feet wrinkles to disappear.


Unintended spread of botulinum toxin into surrounding muscles following injections of Botox is unremarkable when small dosages are used. This is the case with Botulinum toxin injections to the face for cosmetic purposes1,2. One study showed that the area of diffusion was approximately 2.4-6.0 cm2, 3 (at the concentration closest to that which most doctors in Singapore use for botulinum toxin injections)- this means that the likelihood of Botulinum toxin spreading to the heart and lung muscles is extremely low.


2. Lethal dose of Botulinum toxin was injected

What if botulinum toxin diffused from the site of injection and travelled via the bloodstream to the heart and lungs? So far, the manufacturers of Botox, Allergan have stated that it is not possible to detect Botulinum toxin in the bloodstream following injection of Botox into muscles at recommended dosages4.


Although unlikely, let us assume, for the sake of the argument, that Botulinum toxin somehow entered the bloodstream. Logically, for Botulinum toxin to cause a complication like cardiorespiratory failure and death; a lethal dose must be given. Afterall, it is the dose that makes an elixir a poison.


So far, I was not able to locate any studies on the lethal dose for Botox related to cosmetic procedures. Whatever information that can be inferred for toxic or lethal doses are extrapolated from animal studies or in human studies unrelated to aesthetic treatments. One study points to a toxic dose of 39U/kg body weight5.


This would mean that for an average Singaporean female who weighs about 50kg, the toxic dose of botox for her would be 50kg x 39U/kg= 1950 units of Botox- a mammoth amount that most doctors would not administer in one setting. One bottle of Botox contains 100 units- so this means that it would require 20 bottles worth Botox into her! This is unimaginable! In reality, for all the wrinkles of the upper face to be treated- I almost never exceed 40 units of Botox. The likelihood of a patient exceeding 100 units even with the full works of Botox is very rare, in my practice. This dose is hardly close to the lethal dose, so for cardiorespiratory failure to result from aesthetic treatments is very, very unlikely.


One interesting trend about Botulinum toxin is the popularity of Baby Botox or preventive Botox. Essentially, small doses of botulinum toxin are given to remove wrinkles while preserving facial expressions so that the ‘frozen’ or ‘stiff look’ is avoided. In preventive botox, small doses of Botox are given to hyperdynamic muscles to prevent wrinkles from forming. You can read more about this trend in Baby Botox and Preventative Botox in Your 20’s Is Real.



Based on current data, Botulinum toxin, when properly administered by a qualified doctor who respects handling protocols, is very safe for aesthetic dermatological treatments.


4. Can you be allergic to Botox? Can Botox allergy cause death?


As with all drugs, allergy is certainly a possibility. Allergies range from mild reactions like urticaria, (where the skin develops intense itching and wheals) to the other extreme- anaphylaxis. Anaphylaxis is a life threatening condition that causes the airways to narrow and the blood pressure to plummet.


For an allergic reaction like anaphylaxis to develop, the patient must have had prior exposure to the trigger. In this case, let us presume to be Botulinum toxin. It has been reported in the news that this lady was known to have had botulinum toxin injections before. So if she was allergic to botulinum toxin; these allergic reactions would already have been known to her and her doctor. No medical practitioner, who is aware of her allergy would ever administer botulinum toxin.


In the first reported and confirmed case of allergy related to Botox for an aesthetic treatment; the patients was recovered without sequeale6. There is also one reported case of death from Botox due to anaphylaxis. However, this patient was being treated with Botox for neck and back pain and the dose administered was much higher than usually given for approved aesthetic treatments6.


5. So is Botox safe? What are the major side effects of Botulinum toxin injections?


Adverse reactions from Botulinum toxin injections are extremely rare, especially when performed for dermatological or aesthetic treatments by a qualified and experienced doctor.


The uncommon side effects that may occur with Botulinum toxin injections for the face are:

  1. Injection related: mild swelling, redness, bruising, discomfort
  2. Under or over correction
  3. Unintended diffusion of Botox to neighbouring muscles. Botulinum toxin can potentially travel to an adjacent area and may affect the activity of the surrounding muscle. For example; Botox injected into the jaw muscle may potentially travel to the neighbouring smile muscles to affect the smile.
  4. Temporary flu like symptoms or fever (very rare)
  5. Allergy (very rare)

The US FDA has released a review on the safety of Botox injections for aesthetic and medical treatments. Note that the dosages of Botox administered for medical treatments are much higher than dosages for aesthetic treatments. Let’s look at the data.


Over a 13.5 year period from 1989 to 2002; the US FDA received 1437 reports of adverse events related to Botox injections- of which 36 serious events were due to cosmetic treatments8. There were no reports of death from Botox injections related to cosmetic treatments. In these 36 cases of serious events (such as allergic reactions and flu like symptoms) related to cosmetic Botox treatments. For most of these adverse events, there were numerous departures from the recommended Botox dose, dilution, administration, handling, storage and site of injection as advised in the approved labelling8.


I shared about Botulinum toxin and other anti-aging tips in Buro Singapore. You can read the full article Anti-Aging Tips for Every Age here.

Conclusion on Botox/ botulinum toxin safety

I hope that this post was useful in your understanding of Botox and botulinum toxin. Understandably, there has been a lot of fear mongering about the safety of Botox. I hope that by objectively looking at data, we can have a clearer understanding of the controversies. Botulinum toxin, is afterall a very useful drug. If you would like to explore whether Botox injections are suitable for you, please feel free to contact me at my clinic in Singapore or leave a message through the contact form or comments section below.


Bottom line: Botox, like any other medication, should only be administered by a qualified and experienced doctor. In the right hands, it is safe. Always make sure that your doctor or clinic is using an approved brand of botulinum toxin. In Singapore, the three most commonly used brands of botulinum toxin are: Botox, Dysport and Xeomin. These brands have also received US FDA approval. In my experience, all three brands have a very good safety profile and patient satisfaction.


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

Too Much Botox: Botox Gone Wrong

More Than Wrinkes: 5 Surprising Uses for Botox

Shoulder Contouring with Trapezius Botox Injections

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

    REFERENCES   1. Different types of botulinum toxin in humans. Eleopra et al. Mov Disord. 2004;19((Suppl 8):S53–59. 2. 2nd Botulinum toxin type B (MYOBLOC) versus botulinum toxin type A (BOTOX) frontalis study: rate of onset and radius of diffusion. Flynn and Clark.Dermatol Surg. 2003;29:519–522. 3. Effect of volume and concentration on the diffusion of botulinum exotoxin A. Hsu et al.Arch Dermatol. 2004;140:1351–1354. 4. 5. Systemic toxicity of botulinum toxin by intramuscular injection in the monkey. Scott and Suzuki. Mov Disord. 1988; 3:333–335. 6. The First Case Report of a Systemic Allergy to OnabotulinumtoxinA (Botox) in a Healthy Patient. Rosenfield et al. Aesthetic Surgery Journal. 2014 July;34 (5): 766–768. 7. Fatal case of BOTOX-related anaphylaxis? Li et al. J Forensic Sci. 2005 Jan;50(1):169-72. 8. Botulinum toxin type A injections: adverse events reported to the US Food and Drug Administration in therapeutic and cosmetic cases. Cote et al. J Am Acad Dermatol. 2005 Sep;53(3):407-15.



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