Merck Manual

Please confirm that you are not located inside the Russian Federation

honeypot link

Infant Botulism


Larry M. Bush

, MD, FACP, Charles E. Schmidt College of Medicine, Florida Atlantic University

Last full review/revision May 2021| Content last modified May 2021
Click here for the Professional Version

Infant botulism is a potentially life-threatening infection that causes muscle weakness. It develops in infants who eat food containing spores of Clostridium botulinum bacteria.

(See also Overview of Clostridial Infections and Botulism in adults.)

Clostridium botulinum do not require oxygen to live. That is, they are anaerobes.

Clostridia bacteria produce spores. Spores are an inactive (dormant) form of the bacteria. Spores enable bacteria to survive when environmental conditions are difficult. When conditions are favorable, spores grow into bacteria. Clostridia spores grow when they have moisture and nutrients and there is no oxygen, as occurs in the intestine. Thus, if infants consume food containing clostridia spores, the spores grow into bacteria in the intestine and start producing toxins.

Infant botulism occurs most commonly among infants younger than 6 months of age.

The source of the spores in most cases of infant botulism is usually unknown, but some cases have been linked to the ingestion of honey, which may contain spores. Thus, doctors recommend that children under 12 months old should not be fed honey.

Did You Know...

  • Children under 12 months old should not be fed honey because is may contain spores of Clostridium botulinum bacteria.


In about 90% of infants with infant botulism, constipation is the first symptom. Then the muscles become weak, beginning in the face and head and eventually reaching the arms, legs, and muscles involved in breathing. Eyelids droop, crying is weak, and drooling may increase. Infants are less able to suck, and their face loses its expression.

Problems range from being tired and feeding slowly to losing a substantial amount of muscle tone and having difficulty breathing. When infants lose muscle tone, they may feel abnormally limp.


  • Stool tests

Doctors suspect infant botulism based on symptoms.

Detecting the bacteria or the toxins in a sample of an infant’s stool confirms the diagnosis of infant botulism.


  • Botulism immune globulin

Treatment is started as soon as infant botulism is suspected, without waiting for test results.

Infants are hospitalized, and doctors take measures to stabilize them (prevent their condition from worsening), such as use of a mechanical ventilator to assist with breathing.

Infant botulism is treated with botulism immune globulin, which is given slowly by vein. This immune globulin is obtained from human donors who have high levels of antibodies to the botulinum toxin. (Antibodies are proteins produced by the immune system to help defend the body against a particular attacker, such as botulinum toxin.)

Antibiotics are not helpful because the main problem is the toxin that has already been produced by the bacteria.

More Information

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  • Infant Botulism Treatment and Prevention Program: Web site or call 510-231-7600: Provides information about treatment, prevention, and support groups

Drugs Mentioned In This Article

Generic Name Select Brand Names
Gammagard S/D
NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
Others also read

Also of Interest

Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID