Botulism

Content provided by Mayo Clinic

Date Updated: 08/12/2020

Overview

Botulism is a rare but serious condition caused by toxins from bacteria called Clostridium botulinum.

Three common forms of botulism are:

Foodborne botulism. The harmful bacteria thrive and produce the toxin in environments with little oxygen, such as in home-canned food.
Wound botulism. If these bacteria get into a cut, they can cause a dangerous infection that produces the toxin.
Infant botulism. This most common form of botulism begins after Clostridium botulinum bacterial spores grow in a baby's intestinal tract. It typically occurs in babies between the ages of 2 months and 8 months.

All types of botulism can be fatal and are considered medical emergencies.

Symptoms

Foodborne botulism

Signs and symptoms of foodborne botulism typically begin between 12 and 36 hours after the toxin gets into your body. But, depending on how much toxin was consumed, the start of symptoms may range from a few hours to a few days. Signs and symptoms of foodborne botulism include:

Difficulty swallowing or speaking
Dry mouth
Facial weakness on both sides of the face
Blurred or double vision
Drooping eyelids
Trouble breathing
Nausea, vomiting and abdominal cramps
Paralysis

Wound botulism

Signs and symptoms of wound botulism appear about 10 days after the toxin has entered the body. Wound botulism signs and symptoms include:

Difficulty swallowing or speaking
Facial weakness on both sides of the face
Blurred or double vision
Drooping eyelids
Trouble breathing
Paralysis

The wound may or may not appear red and swollen.

Infant botulism

If infant botulism is related to food, such as honey, problems generally begin within 18 to 36 hours after the toxin enters the baby's body. Signs and symptoms include:

Constipation, which is often the first sign
Floppy movements due to muscle weakness and trouble controlling the head
Weak cry
Irritability
Drooling
Drooping eyelids
Tiredness
Difficulty sucking or feeding
Paralysis

Certain signs and symptoms usually don't occur with botulism. For example, botulism doesn't generally increase blood pressure or heart rate, or cause fever or confusion. Sometimes, however, wound botulism may cause fever.

When to see a doctor

Seek urgent medical care if you suspect that you have botulism. Early treatment increases your chances of survival and lessens your risk of complications.

Seeking medical care promptly may also alert public health authorities. They may then be able to keep other people from eating contaminated food. Botulism isn't contagious from person to person.

Causes

Foodborne botulism

The source of foodborne botulism is often home-canned foods that are low in acid, such as fruits, vegetables and fish. However, the disease has also occurred from spicy peppers (chiles), foil-wrapped baked potatoes and oil infused with garlic.

When you eat food containing the toxin, it disrupts nerve function, causing paralysis.

Wound botulism

When C. botulinum bacteria get into a wound — possibly caused by an injury you might not notice — they can multiply and produce toxin. Wound botulism has increased in recent decades in people who inject heroin, which can contain spores of the bacteria. In fact, this type of botulism is more common in people who inject black tar heroin.

Infant botulism

Babies get infant botulism after consuming spores of the bacteria, which then grow and multiply in their intestinal tracts and make toxins. The source of infant botulism may be honey, but it's more likely to be exposure to soil contaminated with the bacteria.

Are there benefits to botulinum toxin?

You might wonder how something so toxic could ever be beneficial, but scientists have found that the paralyzing effect of botulinum toxin makes it useful in certain circumstances.

Botulinum toxin has been used to reduce facial wrinkles by preventing contraction of muscles beneath the skin and for medical conditions, such as eyelid spasms and severe headaches. However, there have been rare occurrences of serious side effects, such as muscle paralysis extending beyond the treated area, with the use of botulinum toxin for medical reasons. Be sure to use a licensed doctor for any cosmetic or medical procedures using onabotulinumtoxinA (Botox).

Complications

Because it affects muscle control throughout your body, botulinum toxin can cause many complications. The most immediate danger is that you won't be able to breathe, which is the most common cause of death in botulism. Other complications, which may require rehabilitation, may include:

Difficulty speaking
Trouble swallowing
Long-lasting weakness
Shortness of breath

Prevention

Use proper canning techniques

Be sure to use proper techniques when canning foods at home to ensure that any botulism germs in the food are destroyed:

Pressure-cook these foods at 250 F (121 C) for 20 to 100 minutes, depending on the food.
Consider boiling these foods for 10 minutes before serving them.

Prepare and store food safely

Don't eat preserved food if its container is bulging or if the food smells spoiled. However, taste and smell won't always give away the presence of C. botulinum. Some strains don't make food smell bad or taste unusual.
If you wrap potatoes in foil before baking them, eat them hot or loosen the foil and store them in the refrigerator — not at room temperature.
Store oils infused with garlic or herbs in the refrigerator.

Infant botulism

To reduce the risk of infant botulism, avoid giving honey — even a tiny taste — to children under the age of 1 year.

Wound botulism

To prevent wound botulism and other serious bloodborne diseases, never inject or inhale street drugs.

Diagnosis

To diagnose botulism, your doctor will check you for signs of muscle weakness or paralysis, such as drooping eyelids and a weak voice. Your doctor will also ask about the foods you've eaten in the past few days, and ask if you may have been exposed to the bacteria through a wound.

In cases of possible infant botulism, the doctor may ask if the child has eaten honey recently and has had constipation or sluggishness.

Analysis of blood, stool or vomit for evidence of the toxin may help confirm an infant or foodborne botulism diagnosis. But because these tests may take days, your doctor's exam is the main way to diagnose botulism.

Treatment

For cases of foodborne botulism, doctors sometimes clear out the digestive system by inducing vomiting and giving medications to induce bowel movements. If you have botulism in a wound, a doctor may need to remove infected tissue surgically.

Antitoxin

If you're diagnosed early with foodborne or wound botulism, injected antitoxin reduces the risk of complications. The antitoxin attaches itself to toxin that's still circulating in your bloodstream and keeps it from harming your nerves.

The antitoxin cannot, however, reverse the damage that's been done. Fortunately, nerves do regenerate. Many people recover fully, but it may take months and extended rehabilitation therapy.

A different type of antitoxin, known as botulism immune globulin, is used to treat infants.

Antibiotics

Antibiotics are recommended for the treatment of wound botulism. However, these medications are not advised for other types of botulism because they can speed up the release of toxins.

Breathing assistance

If you're having trouble breathing, you'll probably need a mechanical ventilator for as long as several weeks as the effects of the toxin gradually lessen. The ventilator forces air into your lungs through a tube inserted in your airway through your nose or mouth.

Rehabilitation

As you recover, you may also need therapy to improve your speech, swallowing and other functions affected by the disease.

Preparing for an appointment

You may first see your primary care doctor. However, you'll likely be sent to the hospital for immediate treatment. At the hospital, you'll probably see several doctors, including those who specialize in neurology (neurologist) and infectious diseases.

What you can do

Bring any medications you take with you, and let your doctor know about any vitamins or supplements you're taking.
Write down questions to ask your doctor. Although you may not have time to write down questions before your first appointment, write down any questions you want to ask at your follow-up appointments.

For botulism, some basic questions to ask your doctor include:

How did I get botulism?
Will I have any lasting problems?
What side effects can I expect from treatment?
Are there dietary restrictions I need to follow?
How can I prevent this from happening again?

Don't hesitate to ask your doctor any other appropriate questions.

What to expect from your doctor

Your doctor is likely to ask you a number of questions, such as:

When did you begin having symptoms?
Have your symptoms been continuous or occasional?
Have you or your child eaten any home-canned food recently?
If your infant is ill, has he or she consumed honey?
Did anyone else eat the food suspected of making you ill?