Botox is an injectable drug made from botulinum toxin type A. This toxin is produced by the bacterium Clostridium botulinum.

Although this is the same toxin that causes botulism — a life-threatening form of food poisoning — its effects vary according to the amount and type of exposure. For example, Botox is only injected in small, targeted doses.

When injected, Botox blocks signals from your nerves to your muscles. This prevents the targeted muscles from contracting, which can ease certain muscular conditions and improve the appearance of fine lines and wrinkles.

Keep reading to learn more about the safety of Botox, common uses, side effects to look out for, and more.

Although botulinum toxin is life-threatening, small doses — such as those used in the application of Botox — are considered safe.

In fact, only 36 cases of adverse effects associated with cosmetic use were reported to the U. S. Food and Drug Administration (FDA) between 1989 and 2003. Thirteen of these cases may have had more to do with an underlying condition than with the drug itself.

With that in mind, some researchers speculate that cosmetic applications may carry less risk than therapeutic Botox injections, as the doses are usually much smaller.

One 2005 study found that adverse effects were more likely to be reported with therapeutic use. This may be related to the underlying condition, or it may be because higher doses are needed to treat the condition.

Still, the overall risk is minimal, and Botox is considered safe overall.

You should always go to a board-certified dermatologist or plastic surgeon for Botox injections. You’re more likely to experience adverse side effects if your injections aren’t prepared according to FDA standards or injected by an inexperienced doctor.

You should wait to receive Botox if you’re pregnant or breastfeeding.

Botox is typically known for its ability to reduce the appearance of wrinkles and fine lines. For example, Botox injections can relax the muscles that cause:

  • crow’s feet, or wrinkles that appear at the outer corner of the eyes
  • frown lines between the eyebrows
  • forehead creases

It’s also used to treat underlying muscular conditions. This includes:

Although Botox injections are relatively safe, minor side effects are possible. These include:

  • pain, swelling, or bruising at the injection site
  • headache
  • fever
  • chills

Some side effects are tied to the area of injection. For example, if you receive injections in the eye area, you may experience:

  • drooping eyelids
  • uneven eyebrows
  • dry eyes
  • excessive tearing

Injections around the mouth may result in a “crooked” smile or drooling.

Most side effects are usually temporary and should fade within a few days.

However, drooping eyelids, drooling, and asymmetry are all caused by the unintentional effects of the toxin on muscles surrounding the target areas of the drug, and these side effects may take several weeks to improve as the toxin wears off.

In rare cases, you may develop botulism-like symptoms. Seek immediate medical attention if you begin experiencing:

  • difficulty speaking
  • difficulty swallowing
  • difficulty breathing
  • vision problems
  • loss of bladder control
  • general weakness

Since the effects of Botox injections are temporary, most people get repeated injections over time. However, research on long-term efficacy and safety is limited.

One 2015 study assessed the effects in participants who received Botox injections every six months to help treat bladder conditions. The researchers capped the observation window at two years.

They ultimately concluded that the risk of adverse effects didn’t increase over time. People who received repeated injections also had better treatment success in the long term.

However, the results of a 2015 review suggest that adverse effects may appear after the 10th or 11th injection.

For example, researchers in one included study observed 45 participants over the course of 12 years. The participants regularly received Botox injections. During this time, 20 cases of adverse side effects were reported. These included:

  • difficulty swallowing
  • drooping eyelid
  • neck weakness
  • nausea
  • vomiting
  • blurred vision
  • general or marked weakness
  • difficulty chewing
  • hoarseness
  • edema
  • difficulty speaking
  • heart palpitations

More research is needed to understand the potential long-term effects.

If you’re considering Botox treatments, it’s important to work with a licensed medical professional. Although it may be cheaper to work with someone who isn’t licensed, doing so can increase your risk for complications. Remember that the toxin lasts three to six months, and you will likely need to return for multiple treatments.

As with any procedure, side effects are possible. Talk to your doctor about what you can expect during the injection process and in the subsequent recovery period. They can answer any questions you may have and discuss your individual benefits and risks.