Pica

Pica is rare in cases, but when it appears the exam tests one instinct above all: medical risk first, then behavioral treatment.

Criteria at exam depth (paraphrased):

• Persistent eating of nonnutritive, nonfood substances (such as paint chips, dirt, clay, hair, paper) over a period of at least 1 month.
• The eating is inappropriate to the person's developmental level; a minimum age of 2 years is suggested, because mouthing objects is normal in infancy.
• The behavior is not part of a culturally supported or socially normative practice.
• If it occurs in the context of another mental disorder (such as intellectual disability or autism spectrum disorder) or a medical condition (including pregnancy), it is severe enough to warrant separate clinical attention.
• Specifier: in remission.

Hinge differentials:

• Developmentally normal mouthing — expected in infants and toddlers.
• Cultural practices — for example, clay or earth eating that is socially sanctioned in some communities.
• Anorexia nervosa — nonnutritive substances (such as tissue) eaten to curb appetite, with weight and shape concerns.
• ARFID — restriction of food rather than ingestion of nonfood items.
• Factitious disorder or self-harm — swallowing objects deliberately to feign illness or injure oneself.

On the NCMHCE: Medical evaluation is essential before and during treatment: risks include lead poisoning, intestinal obstruction or perforation, parasitic infection, and dental injury, and pica is associated with nutritional deficiencies (such as iron deficiency) that should be checked. In pregnancy, refer to the prenatal provider. Treatment priority is safety: environmental modification (remove or secure the items), supervision, and behavioral interventions such as differential reinforcement and teaching replacement behaviors. For children with developmental disabilities, offering developmentally appropriate substitutes for the oral and tactile stimulation the behavior provides is a common strategy. Assess for neglect, low supervision, and environmental hazards (older housing with lead paint), and work with caregivers without blame.

Clinical Pearl: Nonfood eating for at least 1 month, developmentally inappropriate, not culturally sanctioned. Refer for medical evaluation first; then secure the environment and reinforce alternatives.