Botox is used to soften forehead lines, frown lines and crow's feet. Botulinum toxin injections are also used for certain medical conditions, including chronic migraines and excessive sweating.

So, does Botox cause cancer? No. Current medical evidence has not shown that approved Botox injections cause cancer. The FDA-approved prescribing information also reports that Botox Cosmetic tested negative in several genetic toxicology tests.

In this article, we explain the evidence in plain language, including what is known about cancer risk, DNA testing, long-term use and the side effects that are actually associated with Botox.

What Is Botox and How Does It Work?

Botox is a brand name for onabotulinumtoxinA, a purified form of botulinum toxin type A. This substance originates from the bacterium Clostridium botulinum, which produces a toxin responsible for botulism when exposure occurs under harmful conditions.

However, the medically prepared product used for injections is different from exposure to the unprocessed toxin. Approved products are manufactured and controlled for specific medical uses and administered in carefully measured doses.

Botox works by temporarily blocking certain chemical signals that nerves send to muscles. When these signals are interrupted, the targeted muscles relax rather than contracting as strongly as before.

This temporary relaxation can soften wrinkles caused by repeated facial movements, including:

• Forehead lines.
• Frown lines between the eyebrows.
• Crow's feet around the eyes.

Botulinum toxin injections also have medical applications. Depending on the product and approved indication, they may be used to treat chronic migraines, excessive sweating, certain muscle spasms and other conditions.

Learn more in the Cleveland Clinic's overview of Botox injections .

Does Botox Cause Cancer? What Does the Research Say?

No. Current medical evidence does not show that approved Botox injections cause cancer. Botox is not identified as a cancer-causing treatment in the available evidence reviewed for this article.

Botox has been used in medical practice for decades. The research and regulatory information discussed below do not show that cosmetic Botox injections cause cancer. The important point for patients is that there is no established evidence linking approved Botox injections to cancer.

Cancer develops through changes that allow abnormal cells to grow and divide uncontrollably. These changes can involve genetic alterations, environmental exposures, inherited factors and other biological processes.

Botox, on the other hand, is designed to act on nerve signaling and temporarily reduce muscle activity. Its established mechanism of action is different from the processes involved in cancer development.

What does this mean for patients? The available evidence does not show that approved cosmetic Botox injections cause cancer. The FDA's genetic toxicology results are reassuring, while the absence of long-term animal carcinogenicity studies should be understood as a research limitation—not as proof of a cancer risk.

Does Botox Increase the Risk of Skin Cancer?

Another common concern is whether Botox injections can increase the risk of developing skin cancer.

Botox is commonly injected into specific facial muscles to reduce the appearance of expression-related wrinkles. Its primary action involves nerve-to-muscle communication rather than directly treating or altering skin cells.

Skin cancer, meanwhile, is associated with factors such as ultraviolet radiation exposure, certain genetic characteristics, immune status and other environmental influences.

Current evidence has not shown that cosmetic Botox injections increase the risk of skin cancer. Botox is not a substitute for sun protection, skin checks or appropriate dermatologic care.

However, Botox should never be considered a substitute for sun protection or regular skin examinations.

If you notice a suspicious skin change, consult a dermatologist rather than assuming it is related to a previous cosmetic treatment.

Does Botox Affect Your DNA or Cause Genetic Mutations?

The concern that Botox might cause cancer is sometimes connected to questions about DNA damage and genetic mutations.

DNA contains the instructions that help regulate how cells function, grow and divide. Certain genetic changes can contribute to cancer development.

Botox works through a different biological pathway. It temporarily interferes with the release of acetylcholine, a chemical messenger involved in muscle contraction.

The FDA prescribing information reports that Botox Cosmetic tested negative in several genetic toxicology assays, including tests for gene mutations and chromosomal abnormalities.

This is useful evidence when discussing genetic safety. However, it should not be interpreted as proof that every possible biological effect has been investigated.

The available evidence does not show that approved cosmetic Botox injections cause DNA mutations that lead to cancer. The FDA's negative genetic toxicology test results support this conclusion, although no single set of tests can answer every possible long-term research question.

Is Botox Safe for Long-Term Use?

Many people do not receive Botox just once. They return for treatments every few months to maintain their results. Naturally, this raises another question: Is Botox safe if you use it regularly for several years?

Mayo Clinic's September 2016 Q&A on Botox safety discussed the treatment's safety experience. The article described a reassuring safety profile based on the evidence available at that time. It is useful background on Botox safety, although it is not a cancer-specific study.

Mayo Clinic explained that Botox treatment can be discontinued without making wrinkles worse than they were before treatment began.

Its more recent Botox injections guide , updated in November 2024, explains how the treatment works, its medical applications, possible complications and recommended precautions.

According to Mayo Clinic, Botox effects generally last around three to four months, although the duration depends on the condition being treated and individual response.

When someone stops receiving injections, muscle movement gradually returns and expression lines may become visible again. This does not mean Botox has accelerated the aging process.

Nevertheless, long-term safety should be considered individually. Treatment history, dosage, injection frequency, medical conditions and other medications can all matter.

Rather than automatically scheduling repeat treatments, discuss the appropriate dose and interval with your healthcare provider.

What Are the Actual Risks and Side Effects of Botox?

Although the question of cancer receives considerable attention, patients should also understand the side effects and complications that are actually recognized with Botox treatment.

Common Temporary Effects

• Mild pain or tenderness at the injection site.
• Bruising, redness or swelling.
• Headache.
• Flu-like symptoms.
• Temporary drooping of the eyelids or eyebrows.
• Eye dryness or excessive tearing.

These effects are generally temporary, although their duration and severity can vary.

These complications are different from cancer concerns and should not be confused with them.

The Cleveland Clinic Botox guide and Mayo Clinic's Botox information provide additional information about treatment risks and warning signs.

Is Botox Safe for People Who Have Had Cancer?

People with a previous cancer diagnosis may have additional questions about cosmetic treatments.

It is important to distinguish between two different issues:

1. Whether Botox causes cancer.
2. Whether someone with a current or previous cancer diagnosis can safely receive Botox.

These are not the same question.

A 2025 systematic review published in Aesthetic Plastic Surgery, titled Aesthetic Medicine in Oncology: A Systematic Review of Botulinum Toxin, Dermal Fillers, Chemical Peels, and Laser Therapies in Cancer Patient , examined aesthetic treatments in oncology patients. It discussed the use of botulinum toxin for certain treatment-related concerns, including post-treatment deformities and quality-of-life considerations.

However, this review did not investigate whether Botox causes cancer or increases cancer recurrence.

If you have a history of cancer, are undergoing chemotherapy or radiation therapy, or are receiving other cancer treatments, discuss cosmetic injections with your oncologist and the healthcare professional performing the procedure.

Your treatment plan, immune status, medications and recovery needs may influence whether an elective procedure is appropriate.

How to Choose a Safe Botox Provider

Regardless of whether your concern is cancer, long-term effects or temporary side effects, choosing an appropriately qualified provider is an important part of treatment safety.

Frequently Asked Questions About Botox and Cancer