Definition of Mental Disorder

According to DSM-IV, “each of the mental disorders is conceptualized as a clinically significant behavioral or psychological syndrome or pattern that occurs in an individual and that is associated with present distress (e.g., a painful symptom) or disability (i.e., impairment in one or more important areas of functioning) or with a significantly increased risk of suffering death, pain, disability, or an important loss of freedom. In addition, this syndrome or pattern must not be merely an expectable and culturally sanctioned response to a particular event, for example, the death of a loved one. Whatever its original causes, it must currently be considered a manifestation of a behavioral, psychological, or biological dysfunction in the individual. Neither deviant behavior (e.g., political, religious, or sexual) nor conflicts that are primarily between the individual and society are mental disorders unless the deviance or conflict is a symptom of a dysfunction in the individual, as described above.” (DSM–IV–TR (2000) 4th ed., text rev.)

Mental illness is a term that describes a broad range of mental and emotional conditions. Mental illness also refers to one portion of the broader ADA term mental impairment, and is different from other covered mental impairments such as mental retardation, organic brain damage, and learning disabilities. The term ‘psychiatric disability’ is used when mental illness significantly interferes with the performance of major life activities, such as learning, working and communicating, among others.

Someone can experience a mental illness over many years. The type, intensity and duration of symptoms vary from person to person. They come and go and do not always follow a regular pattern, making it difficult to predict when symptoms and functioning will flare-up, even if treatment recommendations are followed. The symptoms of mental illness often are effectively controlled through medication and/or psychotherapy, and may even go into remission. For some people, the illness continues to cause periodic episodes that require treatment. Consequently, some people with mental illness will need no support, others may need only occasional support, and still others may require more substantial, ongoing support to maintain their productivity.

The most common forms of mental illness are anxiety disorders, mood disorders, and schizophrenia disorders.

Many drugs cause mental symptoms; the most common classes of drug causes are

  • CNS-active drugs (eg, anticonvulsants, antidepressants, antipsychotics, sedative/hypnotics, stimulants)
  • Anticholinergics (eg, antihistamines)
  • Corticosteroids

Numerous other therapeutic drugs and drug classes have also been implicated; they include some classes that may not ordinarily be considered (eg, antibiotics, antihypertensive). Drugs of abuse, particularly alcohol, amphetamines, cocaine, hallucinogens, and phencyclidine (PCP), particularly in overdose, are also frequent causes of mental symptoms. Withdrawal from alcohol, barbiturates, or benzodiazepines may cause mental symptoms (eg, anxiety) in addition to symptoms of physical withdrawal.

Patients with a mental disorder may develop a physical disorder (eg, meningitis, diabetic ketoacidosis) that causes new or worsened mental symptoms. Thus, a clinician should not assume that all mental symptoms in patients with a known mental disorder are due to that disorder. The clinician may need to be proactive in addressing possible physical causes for mental symptoms, especially in patients unable to describe their physical health because they have psychosis or dementia.

Patients presenting for psychiatric care occasionally have undiagnosed physical disorders that are not the cause of their mental symptoms but nonetheless require evaluation and treatment. Such disorders may be unrelated (eg, hypertension, angina) or caused by the mental disorder (eg, under nutrition due to inanition resulting from chronic psychosis) or its treatment (eg, hypothyroidism due to lithium, hyperlipidemia secondary to atypical antipsychotics).

(For more information go to: http://www.merckmanuals.com/professional/psychiatric_disorders.html)

ECR Center expedites every aspect of a psychiatric drug trial. It combines global experience in II, III and IV Phases of psychiatric drug development with expertise in brain imaging, laboratory (including PK/PD and Biomarkers) IVRS, central data management, electronic data capture and regulatory issues. Our clinical trial experience includes the following psychiatric indications:

  • Anxiety Disorders
  • Generalized Anxiety Disorder
  • Obsessive-compulsive Disorder (OCD)
  • Panic Disorder
  • Post-traumatic Stress Disorder (PTSD)
  • Social Phobia (Social Anxiety Disorder)
  • Attention Deficit Hyperactivity Disorder (ADHD, ADD)
  • Autism Spectrum Disorder (ASD)
  • Bipolar Disorder (Manic-depressive Illness)
  • Borderline Personality Disorder
  • Depression
  • Eating Disorders
  • Schizophrenia
  • Suicide Prevention