In individuals with autism, schizophrenia, and certain physical disorders (such as Kleine-Levin syndrome), nonnutritive substances may be eaten. In such instances, pica should not be noted as an additional diagnosis.

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.

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 health care provider should test for infection if the person has been eating contaminated soil or animal waste. The Diagnostic and Statistical Manual of Mental Disorders, 5th edition, posits four criteria that must be met for a person to be diagnosed with Pica: