Pica

What Causes Pica?

The precise cause of pica is unclear, and the cause of the behavior may vary from case to case. Studies have suggested that certain medical and psychological conditions may play a role in developing pica. Some risk factors include:

• Nutritional deficiencies. Deficiencies of nutrients or minerals such as iron, zinc, or calcium have been associated with pica in some cases.
• Stress or anxiety
• Abuse or neglect
• Mental health-related issues such as schizophrenia
• Developmental conditions such as autism
• Medical conditions such as sickle cell disease or Prader-Willi syndrome

Is Pica Hereditary?

Research has not yet suggested pica runs in families or can be directly inherited by children from their parents. However, some medical conditions sometimes associated with pica, including sickle cell disease and Prader-Willi syndrome, have a genetic component and can be inherited.

How Is Pica Detected?

Pica commonly affects young children, but the behavior must be differentiated from the normal behavior of infants and toddlers, who frequently put non-food items in their mouths. Although children may accidentally swallow items while engaging in this normal behavior, the behavior is not the same as the compulsive eating seen in pica. Because of this, doctors are discouraged from diagnosing pica in children younger than two.

How Is Pica Diagnosed?

To diagnose pica, doctors look for a pattern of symptoms and risk factors. The diagnostic process will also likely include exams to look for medical conditions that could be causing the symptoms. The whole diagnostic process usually includes physical examinations, tests, and a review of medical and family history.

Diagnostic steps may include:

• A physical exam. This exam aims to rule out specific physical conditions that could be causing the symptoms.
• Blood and laboratory tests. These tests will look at the patient’s blood chemistry for issues, such as infections or nutrient deficiencies, that may be causing the symptoms.
• Other exams and tests. Tests and exams such as magnetic resonance imaging (MRI), computerized tomography (CT), or x-rays may be used to look for intestinal blockages or other internal damage caused by the behavior.
• Psychological assessments. These assessments may take the form of questionnaires or talk sessions with a mental health professional to look for symptoms of pica. The assessment results will be compared to the diagnostic criteria in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) to determine whether an official diagnosis of pica is appropriate.

The DSM-5 diagnostic criteria for pica include:

• Persistent eating of non-food, non-nutritional items for at least one month.
• The person is past the developmental stage where eating non-food items might be expected.
• The behavior is not explained by any accepted cultural or social practices.
• If another mental, developmental, or medical disorder is present, the pica symptoms are severe enough to warrant medical care on their own.

How Is Pica Treated?

Treatment for pica can include treatment of any underlying disorders, treatment of damage caused by ingestion of harmful substances, and behavioral therapy to improve pica behaviors. Treatment approaches can include:

• Dietary supplements to correct any deficiencies
• Treatment for ingestion of toxins (e.g., lead from paint chips)
• Therapies such as behavioral therapy, mild aversive therapy, or differential reinforcement

Medications are typically not used to treat pica.

How Does Pica Progress?

Pica may resolve on its own without treatment. Children often grow out of the behavior, especially when guided to understand the difference between food and non-food items. When pica occurs during pregnancy, it usually resolves when the pregnancy is over. 

In some people, especially those with underlying developmental or mental health conditions, pica may continue long-term if left untreated. In these cases, severe health complications are possible. Potential complications of pica include:

• Iron deficiencies (anemia)
• Constipation
• Electrolyte imbalances
• Bacterial, viral, fungal, or parasitic infections
• Damage to the mouth, teeth, esophagus, or the rest of the digestive tract
• Intestinal blockages

How Is Pica Prevented?

There is no sure way to prevent pica, but managing stress or anxiety may help some people. Treatment of the associated mental health or developmental conditions may also improve pica behaviors.

Pica Caregiver Tips

Many people with pica also suffer from other brain and mental health-related issues, a situation called co-morbidity. Here are a few of the disorders commonly associated with pica:

• Pica is sometimes associated with schizophrenia.
• People with autism are at increased risk of pica.

Pica Brain Science

The cause of pica is not always clear. Still, in many cases, it seems to be the symptom of an underlying condition, such as a nutritional deficiency or a gastrointestinal disorder. However, individual case studies have suggested that sometimes pica behaviors may be a manifestation of a brain-related condition. Possible brain-related triggers include:

• Degenerative brain disease. In at least one case study, lesions that damaged the brain’s frontal lobe appeared to be associated with the persistent, compulsive eating of non-food items.
• Obsessive-compulsive disorder (OCD). Other case studies have associated pica behaviors with OCD. In these studies, patients reported feeling compelled to ingest non-food items and feeling more relaxed after consuming them.

Pica Research

Title: Use of Intrapyloric Botulinum Injections in Children

Stage: Recruiting

Principal investigator: Rachel Rosen, MD, MPH

Boston Children’s Hospital

Boston, MA

This study aims to evaluate the effect of intrapyloric botulinum toxin in children with feeding disorders.

Chronic vomiting and feeding difficulties are common in young children and have a negative physical and psychosocial impact on patients and families. Currently, there is no straightforward treatment algorithm for these issues, and management often involves multiple medication trials and procedures. Intrapyloric botulinum toxin injection has been proposed as a treatment for nausea and vomiting in adults. Still, there is minimal prior research on use in children and no prior research on use in children with feeding disorders. The aims of this study are: (1) to determine the efficacy of intrapyloric botulinum toxin injection for reducing gastrointestinal symptoms in children, (2) to determine the efficacy of intrapyloric botulinum injections for improving feeding outcomes in children, and (3) to define predictors of response to intrapyloric botulinum toxin injection.

Title: Brain Function in Adolescent Eating Disorders and Healthy Peers

Stage: Recruiting

Principal investigator: Christina Wierenga, PhD

University of California, San Diego

San Diego, CA

This study of adolescent eating disorders (ED) will examine the association of temperament-based classifications, brain activation during incentive processing, and ED symptoms at the time of scan and 1 year later to better understand the neurobiology and symptoms of ED. We will recruit 150 females currently ill with an ED and 50 controls ages 14-17 to investigate how temperaments reflecting greater inhibition, impulsivity, or effortful control correspond to 1) clinical symptoms and 2) the brain’s response to anticipation and outcome of salient stimuli, and 3) by collecting follow-up clinical data one year later, identify how temperament-based subtypes predict ED symptom change (e.g., clinical prediction). Data collection will rely on functional magnetic resonance imaging (fMRI) technology.

Title: Pilot of Reconnecting to Internal Sensations and Experiences in Undergraduates (RISE)

Stage: Recruiting

Contact: April R. Smith, PhD

Auburn University

Auburn, AL

Project RISE is a randomized control trial. The intervention consists of four modules that focus on multiple aspects of interoception, including body awareness, body sensations/movement, eating, health and self-care, emotional awareness, and understanding oneself in relation to others. The comparator condition is called “Health Habits” and is matched for time and attention; participants complete modules related to healthy habits such as financial planning, hygiene, stretching, and healthy eating. Variables of interest include self-report measures of interoception, eating pathology, suicidality, physiological measures of interoception (electrocardiograph; ECG; pain tolerance measured via algometer), and an implicit association test (IAT) with death and life stimuli (meant to measure implicit associations with suicidality). The population will be college students with current or past suicidality or low interoception.