Pica

ByEvelyn Attia, MD, Columbia University Medical Center;
B. Timothy Walsh, MD, College of Physicians and Surgeons, Columbia University
Reviewed/Revised Jul 2022
View Patient Education

Pica is persistent eating of nonnutritive, nonfood material for 1 month when it is developmentally inappropriate (eg, pica is not diagnosed in children < 2 years) and when it is not part of a cultural tradition (eg, of folk medicine, religious rites, or common practice, such as ingestion of clay [kaolin] in the Georgia Piedmont).

(See also Introduction to Eating Disorders.)

Patients tend to eat nontoxic materials (eg, paper, clay, dirt, hair, chalk, string, wool). For children < 2 years, this behavior is not considered developmentally inappropriate; children < 2 years frequently mouth and ingest a variety of objects. Pica is also common during pregnancy.

Usually, pica does not cause significant medical harm. However, some patients develop complications such as

Pica itself rarely impairs social functioning, but it often occurs in people with other mental disorders that do impair functioning (eg, autism, intellectual disability, schizophrenia). Swallowing objects in an attempt to cause self-harm or to falsify illness (as occurs in factitious disorder) is not considered pica.

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

Diagnosis of Pica

  • Clinical criteria (1)

Pica is diagnosed when

  • A patient persistently eats nonnutritive, nonfood material for 1 month.

  • Ingestion of these materials is inappropriate for the developmental level of the patient.

  • Ingestion of these materials is not part of a cultural tradition.

  • If ingestion occurs in a patient with another disorder, it is sufficiently persistent and severe to warrant specific treatment.

Pica is not diagnosed in children < 2 years because at that age, eating such materials is considered part of normal development.

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

Sometimes pica is diagnosed when patients have symptoms of intestinal obstruction (eg, severe cramping, constipation), lead poisoning, or parasitic infestation that trigger a trip to the emergency department or a clinician.

Tests may be done based on the patient's symptoms and/or the substances ingested. They include blood tests to check for lead poisoning when paint chips have been eaten and stool tests to detect parasitic infestation when soil has been eaten.

Diagnosis reference

  1. 1. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition Text Revision, DSM-5-TRTM, Feeding and eating disorders.

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 pica.

Nutritional deficiencies and other complications are treated. Intestinal obstruction may require surgery.

Key Points

  • Diagnose pica in patients who persistently eat nonnutritive, nonfood material for 1 month; pica is not diagnosed in children < 2 years.

  • Usually, pica does not cause significant medical harm, but check patients for weight loss and nutritional deficiencies and, if symptoms suggest it, for intestinal obstruction, lead poisoning, and parasitic infestation.

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

  • Treat nutritional deficiencies and other complications as needed.

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