Experts believe that an imbalance of brain chemicals called neurotransmitters is a contributing cause of many mental illnesses that affect teens. Most theories of mental illness posit that genes, brain structure and environmental factors, such as stressful events, all combine to produce a chemical imbalance, which in turn causes psychiatric symptoms. Among the disorders attributed at least in part to a chemical imbalance are attention-deficit hyperactivity disorder, anxiety, depression, bipolar disorder and schizophrenia.
Attention-Deficit Hyperactivity Disorder
A teen with attention-deficit hyperactivity disorder, or ADHD, has difficulty sitting still and paying attention, and often acts and speaks impulsively. This disorder begins in childhood but can persist into adolescence or even adulthood. According to the National Institute of Mental Health, or NIMH, ADHD may be caused in part by an imbalance of the neurotransmitters dopamine, serotonin and adrenaline. To correct this imbalance, the disorder is typically treated with a stimulant medication such as Ritalin, which increases the level of dopamine in the brain.
Anxiety, Depression and Bipolar Disorder
Mood disorders such as anxiety, depression and bipolar disorder are commonly attributed, in part, to an imbalance of the neurotransmitter serotonin or norepinephrine. Treatment for these disorders often includes medications known as selective serotonin reuptake inhibitors, or SSRIs, as well as serotonin-norepinephrine reuptake inhibitors, or SNRIs. These drugs are believed to correct the imbalance in the errant brain chemicals, thereby reducing symptoms of an excessively depressed or elevated mood.
Risks of Antidepressants in Teens
While SSRIs and SNRIs can be very effective in both adults and teens, some SSRIs have been associated with severe side effects in teens, especially suicidal thoughts. A large study funded in part by the NIMH found that teens taking SSRIs were twice as likely to have suicidal thoughts as those taking a placebo. In response, the Food and Drug Administration now requires a "Black Label" warning, the agency's most serious warning, on all antidepressants. This warning states that the drug may increase the risk of suicidal thinking and behavior in patients between the ages of 18 and 25.
Schizophrenia
Teens with schizophrenia experience often "psychosis," which is a state of being out of touch with reality. They can see or hear things that other people don't see or hear, or believe things that are not reality-based. These symptoms result from an imbalance of the neurotransmitters dopamine, glutamate as well as possibly others, according to the NIMH. A variety of antipsychotic medications are used in an attempt to restore this imbalance and reduce the symptoms. These drugs, like SSRIs, have many severe side effects, which can often lead teens to quit taking them.
Controversy
The chemical imbalance theory of mental illness has not been scientifically proven, and there is no test to demonstrate that any individual teen has an imbalance of neurotransmitters. Many skeptics reject this theory, arguing that it was invented by the drug manufacturers in an effort to market their products. As stated by Jonathan Leo, professor of neuroanatomy at Lincoln Memorial University-DeBusk College of Osteopathic Medicine, "The number of people who believe that depressed people have low serotonin is a glorious testament to the power of marketing."
References
- Substance Abuse and Mental Health Services Administration: Evidence-Based Practices: Shaping Mental Health Services Toward Recovery
- MedLinePlus: Attention Deficit Hyperactivity Disorder
- National Institute of Mental Health: Antidepressant Medications for Children and Adolescents: Information for Parents and Caregivers
- National Institute of Mental Health: What Causes Schizophrenia?
- Citizens Commission on Human Rights: Blaming the Brain: The Chemical Imbalance Fraud
