Pica is the persistent eating of substances such as dirt or paint that have no nutritional value.
The Handbook of Clinical Child Psychologycurrently estimates that prevalence rates of pica range from 4%-26% among institutionalized populations. Research among non-institutionalized populations takes the form of individual case studies, making prevalence rates difficult to estimate.
Many people pick at their skin once in a while, but sometimes it crosses the line into a condition called skin picking disorder (excoriation).
When this happens, picking at the skin -- for example, picking a scab or the skin around your nails -- can become so frequent and intense that it causes bleeding, sores, and scars.
Some people with this disorder repeatedly scratch to try to remove what they see as some kind of imperfection in their skin.
If pica is suspected, a medical evaluation is important to assess for possible anemia, intestinal blockages, or potential toxicity from ingested substances. If symptoms are present, the doctor will begin an evaluation by performing a complete medical history and physical exam. The doctor may use certain tests -- such as X-rays and blood tests -- to check for anemia and look for toxins and other substances in the blood, and to check for blockages in the intestinal tract. The doctor also may test for possible infections caused by eating items contaminated with bacteria or other organisms. A review of the person's eating habits also may be conducted.
Before making a diagnosis of pica, the doctor will evaluate the presence of other disorders -- such as mental retardation, developmental disabilities, or obsessive-compulsive disorder -- as the cause of the odd eating behavior. This pattern of behavior must last at least one month for a diagnosis of pica to be made.
How Is Pica Treated?
Given the risk of medical complications (such as lead poisoning) associated with pica, close medical monitoring is necessary throughout treatment of the eating behavior. Additionally, close collaboration with a mental health team skilled in treating pica is ideal for optimal treatment of these complex cases.
The Handbook for Clinical Child Psychology currently supports general behavioral strategies as the most effective treatment approach for pica, with training in which foods are edible and which foods cannot be eaten through the use of positive reinforcement.
What Complications Are Associated With Pica?
There are many potential complications of pica, such as:
Certain items, such as paint chips, may contain lead or other toxic substances and eating them can lead to poisoning, increasing the child's risk of complications including learning disabilities and brain damage. This is the most concerning and potentially lethal side effect of pica
Eating non-food objects can interfere with eating healthy food, which can lead to nutritional deficiencies.
Eating objects that cannot be digested, such as stones, can cause constipation or blockages in the digestive tract, including the intestines and bowels. Also, hard or sharp objects (such as paperclips or metal scraps) can cause tears in the lining of the esophagus or intestines.
Bacteria or parasites from dirt or other objects can cause serious infections. Some infections can damage the kidneys or liver.
Co-existing developmental disabilities can make treatment difficult.