What Is Botox Made Of?

Botox is made from a purified form of botulinum toxin type A, a protein produced by the bacterium Clostridium botulinum, combined with small amounts of human albumin and sodium chloride (salt) and supplied as a dried powder. Before injection, a clinician mixes the powder with sterile saline. Here is what each ingredient is, how the product is made, and why those details matter for your safety.

What is Botox made of?

According to the FDA prescribing information for Botox Cosmetic (onabotulinumtoxinA), each vial contains three ingredients:

Botulinum toxin type A neurotoxin complex. This is the active ingredient. It is a complex of the neurotoxin protein and several accessory proteins.
Human albumin. A protein derived from human blood, used in the formulation.
Sodium chloride. Ordinary salt.

The label describes the vial contents as sterile and vacuum-dried, without a preservative. Vials come in 50-unit and 100-unit sizes, and the amounts of albumin and sodium chloride scale with the vial size. Before use, the powder is reconstituted with sterile, preservative-free 0.9% sodium chloride injection, which is a saline solution.

How is Botox produced?

The label states that Botox Cosmetic is produced from fermentation of the Hall strain of Clostridium botulinum type A. The label then describes a purification process: the toxin is separated from the culture solution through dialysis and a series of acid precipitations, leaving a complex of the botulinum neurotoxin and several accessory proteins. That complex is dissolved in a sterile salt solution containing human albumin, sterile filtered, and vacuum-dried in vials.

Cleveland Clinic notes that healthcare providers use a specific type of the botulinum bacteria (type A) for medical injections, and explains that Botox is produced in a lab, where the botulinum toxin is diluted and sterilized for medical use. The strength of each batch is measured with a potency test specific to the manufacturer's products. That is why the label says Botox units cannot be compared to or converted into units of any other botulinum toxin product.

Is Botox the same toxin that causes botulism?

It comes from the same family of toxins. MedlinePlus describes botulism as a rare but serious illness caused by a toxin made by Clostridium botulinum, and notes that all forms of botulism can be deadly and are medical emergencies. Cleveland Clinic notes that botulinum toxins occur naturally in soil and contaminated food.

A medical product is different from an exposure to the toxin in food or a wound because it is purified, measured in units, and injected in small doses into specific muscles by trained healthcare providers. That does not make it free of risk. The Botox Cosmetic label carries a boxed warning that the effects of the toxin may spread from the injection area and cause symptoms hours to weeks after injection, and that swallowing and breathing difficulties can be life threatening.

Why does the human albumin matter?

Because albumin comes from human blood, the label includes a specific warning. It states that, based on donor screening and manufacturing processes, the product carries a remote risk of transmitting viral diseases and variant Creutzfeldt-Jakob disease, and that no cases of transmission have ever been identified for licensed albumin. If you have concerns about blood-derived ingredients, raise them at your consultation.

The ingredient list also matters for allergies. The label lists an allergy to any botulinum toxin preparation or to any component of the formulation as a reason not to use the product. Other botulinum toxin brands use different formulations, so the ingredient list depends on the product. Tell your clinician about any allergy, and ask which product will be used.

How does it work once injected?

MedlinePlus describes onabotulinumtoxinA as a neurotoxin that blocks the nerve signals that cause muscles to tighten. Cleveland Clinic explains that the injected muscles cannot contract as strongly, and that the effect is temporary, typically lasting several months. Botox Cosmetic is approved by the FDA for adults for the temporary improvement in the appearance of moderate to severe frown lines between the brows, crow's feet, forehead lines, and vertical neck bands called platysma bands. For a plain-language comparison with fillers, read Botox vs dermal fillers.

What side effects can Botox cause?

Side effects vary by treatment area; the FDA label notes that some adverse reactions can last several months or longer. Cleveland Clinic lists possible Botox side effects, which include pain, swelling, redness, or bruising at the injection site, headache, flu-like symptoms, temporary drooping eyelids, and eye irritation or redness. The American Academy of Dermatology (AAD) adds that the injections themselves, rather than the toxin, cause most mild side effects, and that bruising, if it happens, lasts about a week.

The Botox Cosmetic label reports the most common adverse reactions in its clinical studies by treatment area: eyelid drooping (3%) after frown-line treatment, eyelid swelling (1%) after crow's feet treatment, and headache (9%) and brow drooping (2%) after forehead treatment. Ask your clinician which side effects are most likely for the areas in your plan.

Tell your clinician about any side effect that is severe or does not go away. MedlinePlus lists symptoms that need a call to your doctor right away or emergency treatment in the first several weeks after an injection, including vision changes, eyelid swelling, chest pain, an irregular heartbeat, shortness of breath, fainting, rash, or hives. Get emergency care right away for trouble breathing, chest pain, or signs of a severe allergic reaction, and see the emergency symptoms of toxin spread at the end of this article. You or your clinician can also report serious adverse effects to the FDA's MedWatch program.

How can you tell you are getting the genuine product?

In 2024 the FDA warned that counterfeit versions of Botox had been found in multiple states and given to people for cosmetic purposes, with reports of serious symptoms and hospitalizations. Some counterfeit cartons listed the active ingredient as "Botulinum Toxin Type A" instead of "OnabotulinumtoxinA," showed a 150-unit dose that the manufacturer does not make, or used non-English text.

The FDA advises confirming with your healthcare professional that the product comes from an authorized source and that they are licensed and trained to give it. The AAD also warns against buying botulinum toxin online or getting injections in non-medical settings.

When to seek emergency care

Get emergency help right away (call 911 or go to an emergency room) if, after any botulinum toxin injection, you develop difficulty swallowing, breathing, or speaking; a change or loss of voice; muscle weakness all over the body; double or blurred vision; drooping eyelids or brows; or loss of bladder control. MedlinePlus lists these as symptoms that need emergency help, and the FDA advises contacting a health care professional or going to the emergency room for symptoms like these after a botulinum toxin injection.

For more questions to bring to an appointment, see Botox consultation safety questions. To ask about injectable options, use the contact page and ask whether Botox is offered at your location.

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General educational information is not a diagnosis or treatment recommendation. Consult a qualified clinician about your individual circumstances.

What Is Botox Made Of?