Pica

ByEvelyn Attia, MD, Columbia University Medical Center;
B. Timothy Walsh, MD, College of Physicians and Surgeons, Columbia University
Reviewed/Revised Jul 2022 | Modified Sep 2022
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Pica is an eating disorder characterized by regularly eating things that are not food.

  • Usually, what people with pica eat does not harm them, but sometimes what they eat causes complications, such as blockages in the digestive tract or lead poisoning.

  • Doctors usually diagnose pica when a person over age 2 has been eating things that are not food for a month or more.

  • Behavioral modification techniques may help, but little is known about specific treatments for pica.

  • Nutritional deficiencies and other complications are treated as needed.

People with pica regularly eat things that are not food (such as paper, clay, dirt, or hair). For children under 2 years old, this behavior is considered developmentally normal. Young children frequently put all sorts of things in their mouth and sometimes eat them. Pica may also occur during pregnancy.

In some parts of the world, eating things that are not food is part of a cultural tradition, such as folk medicine, religious rites, or common practice. For example, some people in the Georgia Piedmont regularly eat clay.

Usually, what people with pica eat does not harm them. However, sometimes what they eat causes complications, such as constipation, blockages in the digestive tract, lead poisoning from eating paint chips, or a parasitic infection from eating dirt.

Pica itself rarely interferes with social functioning, but it often occurs in people with other mental disorders that do interfere with social functioning. These disorders include autism, intellectual disability, and schizophrenia

Diagnosis of Pica

  • A doctor's evaluation

  • Tests to check for possible complications

Doctors usually diagnose pica by determining what the person has been eating.

Pica is diagnosed when people persistently eat things that are not food for 1 month or longer. The disorder is not diagnosed in children under 2 years old because at that age, eating such materials is not considered abnormal. It is also not diagnosed when eating such materials is part of the person's culture.

If doctors suspect the disorder, they evaluate nutritional status to check for weight loss and nutritional deficiencies.

Sometimes pica is diagnosed when a person has symptoms of a blockage in the digestive tract (such as severe cramping or constipation) or lead poisoning and is taken to the emergency department or to see a doctor.

X-rays may be taken to check for blockages in the digestive tract.

Doctors may do blood tests to check for lead poisoning or stool tests to check for a parasitic infection.

Treatment of Pica

  • Sometimes behavioral modification

  • Treatment of nutritional deficiencies and other complications

Behavioral modification techniques may help, but little is known about specific treatments for this disorder. Behavioral modification techniques help people unlearn undesirable behaviors while learning desirable behaviors.

Nutritional deficiencies and other complications are treated. Blockages in the digestive tract may require surgery.

Pica may last several months, then disappear on its own, particularly in children.

More Information

The following are some English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  1. National Eating Disorders Association (NEDA): Large nonprofit organization that provides access to online screening tools, a helpline, forums, and a variety of support groups (some virtual)

  2. National Association of Anorexia Nervosa and Associated Disorders (ANAD): Access to curricula and training for medical and health care professionals, as well as to peer-to-peer support groups, self-help, and other services to people with eating disorders and their families

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