Stimulant-induced anxiety disorder including amphetamines, methamphetamine or methcathinone

Essential (Required) Features:

• The presentation is characterized by anxiety symptoms (e.g., apprehension or worry, fear, physiological symptoms of excessive autonomic arousal, panic attacks, avoidance behaviour) that develop during or soon after intoxication with or withdrawal from stimulants.
• The intensity or duration of the anxiety symptoms is substantially in excess of anxiety symptoms that are characteristic of Stimulant Intoxication or Stimulant Withdrawal.
• The symptoms are not better accounted for by another mental disorder such as an Anxiety or Fear-Related Disorder, a Depressive Disorder with prominent anxiety symptoms, or Post-Traumatic Stress Disorder. Evidence supporting a diagnosis of another mental disorder would include anxiety symptoms preceding the onset of stimulant use, the symptoms persisting for a substantial period of time after cessation of stimulants or withdrawal (e.g., 1 month or more), or other evidence of a pre-existing mental disorder with anxiety symptoms (e.g., a history of prior episodes not associated with stimulant use).
• The symptoms are not a manifestation of another medical condition.
• The symptoms cause significant distress or significant impairment in personal, family, social, educational, occupational or other important areas of functioning.

When making a diagnosis of Stimulant-Induced Anxiety Disorder, an additional diagnosis indicating the related pattern of stimulant use should also be assigned. These include Episode of Harmful Use of Stimulants, Harmful Pattern of Use of Stimulants, and Stimulant Dependence. A diagnosis of Stimulant Intoxication or Stimulant Withdrawal may also be assigned if applicable.

Additional Clinical Features:

• Stimulant-Induced Anxiety Disorder may present with patterns of symptoms, depending on the specific substance used, that vary according to the characteristics of the user (e.g., genetics, metabolism, personality factors). Stimulants use in higher amounts or over longer periods of time is more likely to be associated with the development of a Stimulant-Induced Anxiety Disorder.
• Symptoms of Stimulant-Induced Anxiety Disorder usually resolve or improve after sustained cessation of stimulant use.
• The duration of Substance Withdrawal for some substances can be protracted. For substances with more protracted withdrawal periods, the onset of symptoms of Substance-Induced Anxiety Disorder can occur up to several weeks after the cessation of substance use. Substance-Induced Anxiety Disorder symptoms related to substances with more protracted withdrawal periods may also last for correspondingly longer periods of time.
• In cases in which multiple psychoactive substance are used, it is often challenging to distinguish which substance is the cause of the Substance-Induced Anxiety Disorder. When the specific etiological substance cannot be determined, a diagnosis of Substance-Induced Anxiety Disorder Due to Multiple Specified Psychoactive Substances including Medications may assigned. In cases of multiple psychoactive substance use in which more than one specific substance can be identified as a cause of the Substance-Induced Anxiety Disorder, the corresponding specific Substance-Induced Anxiety Disorder diagnoses should be given instead.

Boundary with Normality (Threshold):

• Symptoms of Stimulant-Induced Anxiety Disorders should be differentiated from known side effects of psychoactive medication that are not significantly impairing or distressing and from transient physiological aftereffects of intoxication (‘hangover effect’). The duration or severity of the symptoms in Stimulant-Induced Anxiety Disorders must be in excess of side effects (e.g., transient jitteriness as a side effect of methylphenidate) or ‘hangover effects’ of Stimulants and result in significant distress or impairment of functioning.

Boundaries with Other Disorders and Conditions (Differential Diagnosis):

• Boundary with Stimulant Intoxication and Stimulant Withdrawal including Amphetamines, Methamphetamine or Methcathinone: Mental or behavioural symptoms that occur during Stimulant Intoxication or Stimulant Withdrawal should only be used as a basis for diagnosing a Stimulant-Induced Anxiety Disorder if the intensity or duration of the symptoms is substantially in excess of those that are characteristic of Stimulant Intoxication or Stimulant Withdrawal and the symptoms are sufficiently severe to warrant specific clinical attention.
• Boundary with Episode of Harmful Use of Stimulants, Harmful Pattern of Use of Stimulants, or Stimulant Dependence including Amphetamines, Methamphetamine or Methcathinone: The impact of repeated or continuous use of stimulants characteristic of Harmful Pattern of Use of Stimulants and Stimulants Dependence may include Stimulant-Induced Anxiety Disorder. Stimulant-Induced Anxiety Disorders can also be associated with a single episode of stimulant use. In such cases, a Stimulant-Induced Anxiety Disorder should be diagnosed together with a primary diagnosis of Episode of Harmful Use of Stimulants, Harmful Pattern of Use of Stimulants, or Stimulant Dependence.
• Boundary with mental disorders not induced by stimulants including amphetamines, methamphetamine or methcathinone: Stimulant-Induced Anxiety Disorders are differentiated from mental disorders with similar features that are not induced by stimulants on the basis of their onset, course and clinical features. A diagnosis of Stimulant-Induced Anxiety Disorder requires evidence from history, physical or mental examination, or laboratory findings of recent stimulant use, intoxication or withdrawal. Most Stimulant-Induced Mental Disorders resolve or improve within several weeks of cessation of stimulant use. Mental disorders not induced by stimulants may precede the onset of stimulant use or may continue to be symptomatic during periods of sustained abstinence. The co-occurrence of stimulant use or withdrawal and onset of symptoms of mental disorders should not be taken as evidence for a presumptive diagnosis of a Stimulant-Induced Anxiety Disorder. Some people use substances to suppress symptoms of mental disorders (e.g., Schizophrenia and Other Primary Psychotic Disorders, Mood Disorders, Anxiety and Fear-Related Disorders, Personality Disorders) and full symptomatic presentations only emerge upon cessation or reduction in substance use. Furthermore, stimulant use can exacerbate symptoms or precipitate an episode of a pre-existing mental disorder. Finally, stimulant use may be associated with but not aetiologic for new onset of symptoms of a mental disorder. Although a diagnosis of a Stimulant-Induced Anxiety Disorder should not be assigned under these circumstances, an additional diagnosis of Episode of Harmful Use of Stimulants, Harmful Pattern of Use of Stimulants, or Stimulant Dependence may still be appropriate.