Case 16 – A 19-year-old man with substance abuse

A 19-year-old student is being evaluated at his student health center. The physician notes the young man is tachycardic at 101/min with a blood pressure of 145/93 mm Hg. His pupils are constricted and there is a fine tremor in his hands. The patient appears agitated and is sweating. The student says he is just anxious about upcoming final examinations, but when questioned further he becomes angry and belligerent. He finally admits that for the past 2 weeks he has been taking pills his roommate gave him in order to help him stay awake. He says they improve his concentration and allow him to get by on only a few hours of sleep. He has not been eating as much and says his clothes are fitting more loosely on him. He does not see a problem with this, saying many people in the dormitory do the same thing, and that he will stop taking the pills after his examinations are done. The rest of the physical examination is unremarkable. On mental status examination he is alert and oriented to person, place, and time. He is mildly uncooperative, and his speech is rapid. He describes his mood as “terrific,” but his affect is angry. He denies suicidal or homicidal ideation, perceptual disturbances, or delusions. He does not have a prior history of mental illness.

What is the most likely diagnosis?

Amphetamine intoxication. He admits to recent use of pills acquired from his roommate to help him study. Although it is not known exactly what kind of pills he has been taking, the illicit use of dextroamphetamines is a significant problem on college campuses. He exhibits many of the diagnostic criteria found in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) for amphetamine intoxication: he has not been sleeping or eating regularly and there is evidence of recent weight loss; his pulse and blood pressure are elevated, his pupils are dilated, and a tremor is present. He also exhibits behavioral and psychological changes of euphoria, anxiety, tension, and anger. Abuse of stimulants may also result in symptoms of psychosis such as paranoid delusions.

What are the DSM-IV-TR criteria for substance abuse?

The criteria for substance abuse can be remembered using the mnemonic HARP:

1. Hazardous use (eg, driving while intoxicated)
2. Arrests (legal problems)
3. Role failure (repeated work absences due to substance use)
4. Persistent use despite consequences

Only one of these four criteria need be met during a 12-month period. Still, this patient does not meet the criteria for substance dependency. The criteria for substance dependence can be remembered using the mnemonic WITHDrawIT:

1. Withdrawal
2. Interest or important activities given up or reduced
3. Tolerance
4. Harm (physical and psychosocial) with continued use
5. Desire to cut down or control use
6. Intended time/amount of use exceeded
7. Time spent obtaining/using the substance is increased

Three of these seven criteria must be met within a 12-month period to diagnose substance dependency.

What would happen if the patient suddenly stopped taking the pills?

Amphetamine withdrawal is characterized by fatigue, depression, nightmares, headache, profuse sweating, muscle cramps, and hunger. Withdrawal symptoms such as intense dysphoria usually peak in 2-4 days and resolve within 1 week.

Is treatment necessary for patients in amphetamine withdrawal?

Since amphetamine intoxication and withdrawal are generally self-limiting, no specific treatment is necessary. Benzodiazepines (eg, diazepam, lorazepam) can be used to treat agitation or anxiety, but have their own abuse potential. Therapeutic drugs to treat the withdrawal are not routinely used in clinical practice.

By Kristen Vierregger, University of Pennsylvania School of Medicine, Class of 2008; in association with Le TT, Schabelman E, Shivaram A, and Klein J, eds: First Aid Cases for the USMLE Step 2 CK. New York: McGraw-Hill, 2007.