Substance – Induced Mood Disorder Differential Diagnosis
Mood symptoms occur commonly in Substance Intoxication and Substance Withdrawal, and the diagnosis of the substance-specific intoxication or substance-specific withdrawal will usually suffice to categorize the symptom presentation. A diagnosis of Substance-Induced Mood Disorder should be made instead of a diagnosis of Substance Intoxication or Substance Withdrawal only when the mood symptoms are judged to be in excess of those usually associated with the intoxication or withdrawal syndrome and when the mood symptoms are sufficiently severe to warrant independent clinical attention. For example, dysphoric mood is a characteristic feature of Cocaine Withdrawal. Cocaine-Induced Mood Disorder should be diagnosed instead of Cocaine Withdrawal only if the mood disturbance is substantially more intense than what is usually encountered with Cocaine Withdrawal and is sufficiently severe to be a separate focus of attention and treatment.
If substance-induced mood symptoms occur exclusively during the course of a delirium, the mood symptoms are considered to be an associated feature of the delirium and are not diagnosed separately. In substance-induced presentations that contain a mix of different types of symptoms (e.g., mood, psychotic, and anxiety symptoms), the specific type of Substance-Induced Disorder to be diagnosed depends on which type of symptoms predominates in the clinical presentation.
A Substance-Induced Mood Disorder is distinguished from a primary Mood Disorder by the fact that a substance is judged to be etiologically related to the symptoms.
A Substance-Induced Mood Disorder due to a prescribed treatment for a mental disorder or general medical condition must have its onset while the person is receiving the medication (e.g., antihypertensive medication) or during withdrawal, if there is a withdrawal syndrome associated with the medication. Once the treatment is discontinued, the mood symptoms will usually remit within days to several weeks (depending on the half-life of the substance and the presence of a withdrawal syndrome). If symptoms persist beyond 4 weeks, other causes for the mood symptoms should be considered.
Because individuals with general medical conditions often take medications for those conditions, the clinician must consider the possibility that the mood symptoms are caused by the physiological consequences of the general medical condition rather than the medication, in which case Mood Disorder Due to a General Medical Condition is diagnosed. The history often provides the primary basis for such a judgment. At times, a change in the treatment for the general medical condition (e.g., medication substitution or discontinuation) may be needed to determine empirically for that person whether the medication is the causative agent. If the clinician has ascertained that the disturbance is due to both a general medical condition and substance use, both diagnoses (i.e., Mood Disorder Due to a General Medical Condition and Substance-Induced Mood Disorder) may be given. When there is insufficient evidence to determine whether the mood symptoms are due to a substance (including a medication) or to a general medical condition or are primary (i.e., not due to either a substance or a general medical condition), Depressive Disorder Not Otherwise Specified or Bipolar Disorder Not Otherwise Specified would be indicated.