Delusional disorder is characterized by at least how long of delusions, with no hallucinations and normal functioning?

• A. At least 1 month
• B. At least 3 months
• C. At least 6 months
• D. At least 1 week

Answer: (A)

Delusional disorder is diagnosed when one or more delusions are present for a duration of at least one month, and outside of the delusion the person’s functioning is not markedly impaired, with no prominent hallucinations. This duration requirement helps distinguish it from other psychotic disorders that either have shorter episodes or broader symptom profiles.

If the delusions last less than a month, the presentation would be more consistent with a brief psychotic disorder. If symptoms extend from one to six months and are more expansive or include other psychotic features, schizophreniform disorder becomes a consideration. When symptoms persist for six months or longer with broader impairment, schizophrenia is the more likely diagnosis. Therefore, the necessary duration is at least one month.