Pica is a pattern of eating non-food materials (such as dirt or paper).
Causes, incidence, and risk factors
Pica is seen more in young children than adults. Between 10 and 32% of children ages 1 - 6 have these behaviors.
Pica can occur during pregnancy. In some cases, conditions due to a lack of certain nutrients, such as iron deficiency anemia and zinc deficiency, may trigger the unusual cravings. Pica may also occur in adults who crave a certain texture in their mouth.
Children and adults with pica may eat:
- Animal feces
This pattern of eating should last at least 1 month to fit the diagnosis of pica.
Signs and tests
There is no single test that confirms pica. However, because pica can occur in people who have lower than normal nutrient levels and poor nutrition (malnutrition), the health care provider should test blood levels of iron and zinc.
Blood tests can also be done to test for anemia. Lead levels should always be checked in children who may have eaten paint or objects covered in lead-paint dust to screen for lead poisoning.
The health care provider should test for infection if the person has been eating contaminated soil or animal waste.
Treatment should first address any missing nutrients or other medical problems, such as lead exposure.
Treatment involves behavioral, environmental, and family educational approaches. Other successful treatments include associating the pica behavior with bad consequences or punishment (mild aversion therapy) followed by positive reinforcement for eating the right foods.
Medications may help reduce the abnormal eating behavior, if pica occurs as part of a developmental disorder such as mental retardation.
Treatment success varies. In many cases, the disorder lasts several months, then disappears on its own. In some cases, it may continue into the teen years or adulthood, especially when it occurs with developmental disorders.
Calling your health care provider
Call your health care provider if you notice that a child (or adult) often eats non-food materials.
There is no specific prevention. Getting enough nutrition may help.
Boris NW, Dalton R. Vegetative disorders. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 22.
Brittenham GM. Disorders of iron metabolism: Iron deficiency and iron overload. In: Hoffman R, Benz EJ, Shattil SS, et al, eds. Hematology: Basic Principles and Practice. 5th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2008:chap 36.
Reviewed By: Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine; Michelle Benger Merrill, MD, Instructor in Clinical Psychiatry, Department of Psychiatry, Columbia University Medical Center, New York, NY. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.