Mental illness is a serious condition, and should be treated as such. Individuals who think they may suffer from mental illness should consult with a qualified medical practitioner.

Individuals who have suicidal or homicidal plans, and who intend to carry out those plans in the near future should immediately call a trusted friend / family member, a mental health hotline, or the local medical emergency number. Such individuals should also immediately consult with their doctor.

A statement released by the American Psychological Association states that an individual requires specialized training to use the DSM.

An individual's diagnosis according to the DSM may influence their level of qualification for certain mental health services, type of medication prescribed, and even legal status. For this reason, the American Psychiatric Association recommends that clinicians carefully evaluate a patient before making a diagnosis according to the DSM-IV-TR.

There is currently debate about what the DSM-IV-TR classifies as "subclinical behavior," namely thoughts and attitudes that do and do not currently warrant a diagnosis and whether these account for problem behaviors. At times, the threshold for diagnosis may be considered too high, and at other times, it may be considered too low. For instance, the DSM-IV-TR considers individuals who frequently make plans to molest children, but who do not follow through with those plans, subclinical. On the other hand, many individuals diagnosed with Asperger disorder, a mild form of autism, lead fairly normal lives and enjoy many satisfying social relationships.

Many of the individuals who participate in congresses for the DSM have ties to pharmaceutical companies. Critics hold that these individuals have an inherent interest in creating as many diagnoses as possible, because pharmaceutical research to treat a condition occurs as soon as a diagnosis is made.

Because a majority of the mental health professionals who write and revise the DSM are white, middle-upper and upper class individuals, many patients who come from socio-cultural backgrounds other than those of a majority of the book's authors, may be misdiagnosed. What is considered psychologically normal varies according to culture. For example, seeing ghosts after the death of a loved one may or may not be acceptable in a particular culture. For individuals native to the white upper-middle and upper class of the United States, this behavior might warrant psychological evaluation and treatment. Some other communities in the country, however, may consider it completely normal and even healthy.