Methamphetamine and Mental Health

Overview (PDF)
Presentation (PDF)
Printable clinician guide (PDF)

Receiving the correct diagnosis for people with serious mental illness and/or those with Methamphetamine use disorder is critical. Delayed treatment, suboptimal treatment and failure to treat the underlying issue all serve to increase suffering and impede recovery. With the prospect of individuals facing significant legal consequences, such as civil commitment as chemically dependent, mentally ill, or mentally ill and dangerous, it is critical that clinicians be skilled at differential diagnosis for Methamphetamine and mental illness.

The problem

A recent survey found that over half of psychologists, psychiatrists and forensic examiners as well as a mix of treatment providers and other staff within State Operated Forensic Services have encountered cases in which errors were made by practitioners in attributing a client's presentation to mental illness rather than substance use. Further, four in ten have encountered situations in which inaccurately attributing a client's presentation to mental illness rather than substance use has resulted in significant implications, such as loss of liberty, civil commitment.

Survey results (PDF)
Similarities in presentation
Effects Methamphetamine may share with psychotic disorders and bipolar disorder:
- Hallucinations
- Delusions
- Paranoia
- Grandiosity
- Increased energy
- Elevated mood
- Increased goal-directed activity
- Irritability
- Impulsivity
- Decreased need for sleep
- Increased periods of wakefulness
Differences in presentation
Methamphetamine and mental illness can differ in a number of important ways:
- The onset of psychosis tends to be sudden in methamphetamine use. People diagnosed with schizophrenia typically experience a prodromal stage.
- Most psychotic disorders and bipolar disorder generally develop during late adolescence or early adulthood, though delusional disorder can occur later in life. Psychosis secondary to methamphetamine use can occur at any age.
- Visual and tactile hallucinations are more common in methamphetamine psychosis than in schizophrenia. Methamphetamine users may complain of bugs crawling under their skin.
- Negative symptoms (e.g., social withdrawal, impoverishment of speech, flat affect) do not typically occur with methamphetamine use.
- Disorganized speech and thinking is less common in with methamphetamine use. Methamphetamine intoxication is associated with physiological effects, such as increased heart rate and dilated pupils.
Differential diagnosis
Consider the following methods to determine the etiology of the presentation:
- Toxicology screening can help determine if a patient has taken methamphetamine within the past several days, though the effects can extend after the substance has left the system.
- Look for physical signs associated with the use of methamphetamine, such as sores, scabs, injection marks and damage to teeth.
- Look for physiological signs of methamphetamine intoxication, including dilated pupils, increased heart rate, irregular blood pressure, high blood temperature, grinding teeth and twitching.
- Take a thorough history of the patient’s mental health and substance use. Ask specifically about methamphetamine use.
- Construct a timeline to determine if symptoms occur solely during periods of use, though be cautious as patients may not be forthcoming.
- Consider the patient’s age and course of presentation. Methamphetamine psychosis can occur at any age and has rapid onset.
- Look for rare forms of hallucinations, such as tactile hallucinations, which are more common in methamphetamine use. Complaints of insects under the skin are common with methamphetamine use.
- Be cautious in diagnosing psychotic or mood disorders within a year of use.
- Methamphetamine users can appear more insightful, especially outside of periods of methamphetamine intoxication.
- Though often treated with the same medications regardless of etiology, psychosis secondary to methamphetamine use does not typically return after medications are discontinued.