Pica is a pattern of eating non-nutritive substances (such as dirt or paper), lasting for at least one month.

Causes, incidence, and risk factors

Pica is seen more in young children than adults, with 10-32% of children aged 1 to 6 exhibiting these behaviors.

Pica can occur during pregnancy. In some cases, specific nutritional deficiencies, 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.


Pica is the eating of non-food substances. Clay, dirt, ice, sand, animal feces, paint, and hairballs are just a few examples of what children and adults with pica have been known to eat.

Signs and tests

There is no single test that confirms pica, but because pica is associated with abnormal nutritient levels and in some cases malnutrition, blood levels of iron and zinc should be tested.

Hemoglobin can also be checked to test for anemia. Lead levels should always be checked in children who may have eaten paint or objects covered in lead-paint dust. The presence of infection may be detected if contaminated soil or animal waste is being ingested.


First, any nutritional deficiencies and other medical problems, such as lead toxicity, should be addressed.

Treatment emphasizes psychosocial, environmental, and family guidance approaches. Other successful treatments include mild aversion therapy (associating the pica behavior with bad consequences or punishment) followed by positive reinforcement for appropriate eating.

Medications may help reduce the abnormal eating behavior, if pica occurs in the course of a developmental disorder such as mental retardation or pervasive developmental disorder.

Expectations (prognosis)
Treatment success varies. In many cases, the disorder lasts several months, then resolves spontaneously. In some cases, it may continue into adolescence or adulthood, particularly when associated with developmental disorders.


  • malnutrition  
  • lead toxicity  
  • infection  
  • bezoar (a hardened mass of the substance in the stomach)  
  • intestinal obstruction

Calling your health care provider
Call your health care provider if you notice that a child (or adult) has a persistent tendency to eat non-nutritive substances.

There is no specific prevention. Adequate nutrition may be helpful.

Johns Hopkins patient information

Last revised: December 3, 2012
by Gevorg A. Poghosian, Ph.D.

Medical Encyclopedia

  A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | 0-9

All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.