Amphetamine-Related Psychiatric Disorders

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Amphetamine-Related Psychiatric Disorders

Background: The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) describes the following 10 amphetamine-related psychiatric disorders:

1. Amphetamine-induced anxiety disorder

2. Amphetamine-induced mood disorder

3. Amphetamine-induced psychotic disorder with delusions

4. Amphetamine-induced psychotic disorder with hallucinations

5. Amphetamine-induced sexual dysfunction

6. Amphetamine-induced sleep disorder

7. Amphetamine intoxication

8. Amphetamine intoxication delirium

9. Amphetamine withdrawal

10. Amphetamine-related disorder not otherwise specified

These disorders can be induced with either prescription or illegally manufactured amphetamines. Although a controlled substance, a potential exists for abuse, especially in persons with alcoholism or substance abuse.

The substance 3,4-methylenedioxymethamphetamine (MDMA) is a popular recreational stimulant, commonly referred to as ecstasy, which was manufactured legally in the 1980s. MDMA has the desired effects of euphoria, high energy, and social disinhibition lasting 3-6 hours. The drug often is consumed in dance clubs where users dance vigorously for long periods, sometimes causing toxicity and dehydration. Several other amphetamine derivatives exist, such as para-methoxyamphetamine (PMA), 2,5-dimethoxy-4-bromo-amphetamine (DOB), methamphetamine (crystal meth), and 3,4-methylenedioxyamphetamine (MDA). Crystal meth is the pure form of methamphetamine, and because of a low melting point, it can be injected.

The symptoms of amphetamine-induced psychiatric disorders can be differentiated from related primary psychiatric disorders by time. If symptoms do not resolve within 2 weeks of discontinuation of amphetamines, a primary psychiatric disorder should be suspected. Depending upon the severity of symptoms, symptomatic treatment can be delayed to clarify the etiology.

Amphetamine-induced psychosis (delusions and hallucinations) can be differentiated from psychotic disorders when symptoms resolve after amphetamines have been discontinued. Absence of first-rank schneiderian symptoms, including anhedonia, avolition, amotivation, and flat affect, further suggests the diagnosis of amphetamine-induced psychosis. The symptoms of amphetamine use may be indistinguishable from those associated with the use of cocaine. Amphetamines, unlike cocaine, do not cause local anesthesia and have a longer psychoactive duration.

Frequency: In the US: Psychosis, delirium, mood symptoms, anxiety, insomnia, and sexual dysfunction are considered rare adverse effects of therapeutic doses of prescription amphetamines. Dextroamphetamine has a slightly higher rate of these adverse effects due to higher CNS stimulation.

Data from the 1998 National Household Survey on Drug Abuse show that 4.4% of people aged 12 years and older report use during their lifetime, 0.7% report use over the past year, and 0.3% report use over the past month.

Data on the frequency of amphetamine-related psychiatric disorders are unreliable because of comorbid primary psychiatric illnesses.

Intravenous use occurs more frequently in people of lower socioeconomic status.

Internationally: Khat, which is primarily used in Ethiopia for cultural and religious purposes, has been well studied. A house-to-house survey of 10,468 adults showed a lifetime prevalence of khat use of 55.7%. Daily use occurred among 17.4%, and 80% indicated they used khat to increase concentration during prayer.

Khat dependency has been associated with people of Muslim religion and people of lower socioeconomic status.

Race: Amphetamine-related psychiatric disorders occur most commonly in white individuals.

Sex: With intravenous use, amphetamine-related psychiatric disorders occur most commonly in males, with a male-to-female ratio of 3:1 or 4:1.

Age: Amphetamine-related psychiatric disorders occur most frequently in people aged 20-39 years who are inclined to abuse amphetamine derivatives at rave parties and dance clubs.

Adolescents have developed a method of abuse for prescription amphetamines in which prescription tablets are crushed into a powder and ingested nasally.

DSM-IV criteria for amphetamine intoxication Patient recently has used an amphetamine or related substance such as methylphenidate. Clinically significant maladaptive behavioral or psychological changes develop during or shortly after use of amphetamine or a related substance. Changes include the following:

Euphoria or affective blunting

Changes in sociability

Hypervigilance

Interpersonal sensitivity

Anxiety, tension, or anger

Stereotyped behaviors

Impaired judgment

Impaired social or occupational functioning

Two or more of the following develop during or shortly after use of amphetamine or related substance:

Tachycardia or bradycardia

Pupillary dilatation

Elevated or lowered blood pressure

Perspiration or chills

Nausea or vomiting

Evidence of weight loss

Psychomotor agitation or retardation

Muscular weakness, respiratory depression, chest pain, or cardiac arrhythmias

Confusion, seizures, dyskinesias, dystonias, or coma

The symptoms are not due to a general medical condition and are not better accounted for by another mental disorder.

DSM-IV criteria for amphetamine withdrawal

Patient recently has ceased or reduced heavy or prolonged use of amphetamine or related substances. Dysphoric mood and 2 or more of the following physiologic changes develop within a few hours to several days after cessation or reduction of use:

Fatigue

Vivid, unpleasant dreams

Insomnia or hypersomnia

Increased appetite

Psychomotor retardation or agitation

The above-mentioned symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.

The symptoms are not due to a general medical condition and are not better accounted for by another mental disorder.

Physical: A full physical and neurologic examination should take place. Initially, assess patients for medical stability and then for level of danger. During the physical examination, assess for medical complications of amphetamine abuse, including hyperthermia, dehydration, renal failure, and cardiac complications. During the neurologic examination, assess for neurologic complications of amphetamine abuse, including subarachnoid and intracranial hemorrhage, delirium, and seizures. Mental status examination should emphasize delusions, hallucinations, suicide, homicide, orientation, insight and judgment, and affect.

Treatment.

Several different psychiatric conditions can be associated with amphetamine intoxication and withdrawal, all of which may require different management. However, amphetamine-related psychiatric disorders typically are self-limited and usually remit on their own.

Amphetamine-related psychiatric disorders occur most often during intoxication; therefore, treatment should focus on controlling medical and psychiatric symptoms while eliminating the offending substance. Medical therapy involves stabilizing agitation and minimizing psychosis. Gastric lavage removes the amphetamines directly before they have a chance to be absorbed. Medication and charcoal eliminate amphetamines from the gastrointestinal and circulatory systems.

Antipsychotics help control psychotic symptoms and provide rapid tranquilization in the agitated psychotic patient.

Benzodiazepines primarily used to sedate agitated patients. Caution must be used in the violent aggressive patient in whom benzodiazepines may cause disinhibition.

Opiate antagonists [Naloxone] inhibit action of opiates.

Beta-blockers [Propranolol] is useful in patients who are agitated, anxious, and hyper-arousable from amphetamines. They are used temporarily until the amphetamine has been eliminated from the system. For some patients, anxiety can be prolonged, and nonaddictive beta-blockers may be helpful.

Adsorbents placed through a nasogastric tube into the stomach to absorb substances ingested intentionally and accidentally to prevent further absorption into systemic circulation.

Prognosis: Prognosis depends upon the severity of psychiatric impairment and medical complications. Overall, the prognosis is good, with abstinence occurring after the initial psychiatric impairment. Prognosis is worse if personality disorders are present.