• An estimated 16 million people inject drugs worldwide, based on data from 148 countries. The largest numbers of injectors are in China, the United States, and Russia.1



  • From 2000 to 2002, 1.5% of the U.S. population older than the age of 12 years reported injection-drug use at any time; 0.19% reported injection-drug use within the last year—440,000 persons.3
  • Prevalence was highest in persons ages 35 to 49 years (3.5%); higher in men than women (2.0% vs. 1.0%); and higher in whites (1.7%) than African Americans (0.8%) or Hispanics (0.8%).3
  • In 2002, the mean age of injection-drug users (IDUs) was 36 years compared to 21 years in 1979.3
  • Needle sharing is common. In the previous 3 months, 46% of IDUs lent a person a used syringe4 and 54% injected with a used syringe.5
  • There were 27,8371-278,371 meant? substance-abuse treatment admissions for injection-drug use (14.2% of all admissions reported to Substance Abuse and Mental Health Services Administration's [SAMHSA] Treatment Episode Data Set for 2009).6
  • The most commonly injected drug is heroin. Amphetamines, buprenorphine, benzodiazepines, cocaine, and barbiturates also are injected.7
  • HIV prevalence among IDUs is estimated to be 20% to 40%.1
  • The 2009 Monitoring the Future Survey showed that 2.5% of 12th-grade boys in the United States were using anabolic steroids (Figure 240-2).8
  • Anabolic steroid abuse among athletes may range between 1% and 6%.8
  • Some adolescents abuse steroids as part of a pattern of high-risk behaviors. These adolescents also take risks such as drinking and driving, carrying a gun, driving a motorcycle without a helmet, and abusing other illicit drugs.8



Comprehensive management includes acute treatment and continuing care. Relapse is common, but involvement in a treatment program improves outcomes.


Complications of Injecting Drug Use

  • Local problems—Abscess (Figures 240-2 
    Image not available.

    A 32-year-old woman with type 1 diabetes developed large abscesses all over her body secondary to injection of cocaine and heroin. Her back shows the large scars remaining after the healing of these abscesses. (Courtesy of ­Richard P. Usatine, MD.)

    and 240-3; Abscess), cellulitis, septic thrombophlebitis, local induration, necrotizing fasciitis, gas gangrene, pyomyositis, mycotic aneurysm, compartmental syndromes, and foreign bodies (e.g., broken needle parts) in local areas.2
    • IDUs are at higher risk of getting methicillin-resistant Staphylococcus aureus(MRSA) skin infections that the patient may think are spider bites (Figure 240-4).
    • Some IDUs give up trying to inject into their veins and put the cocaine directly into the skin. This causes local skin necrosis that produces round atrophic scars (Figure 240-5).
  • IDUs are at risk for contracting systemic infections, including HIV and hepatitis B or hepatitis C.
    • Injecting drug users are at risk of endocarditis, osteomyelitis (Figures 240-6and 240-7), and an abscess of the epidural region. These infections can lead to long hospitalizations for intravenous antibiotics. The endocarditis that occurs in IDUs involves the right-sided heart valves (see Chapter 50, Bacterial Endocarditis).2 They are also at risk of septic emboli to the lungs, group A β-hemolytic streptococcal septicemia, septic arthritis, and candidal and other fungal infections.


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Question 1 of 1

A 42-year-old African-American man has been diagnosed with hypertension for the past 10 years and treated with medication. One morning, he is found unresponsive by his wife. He is taken to the emergency department and pronounced dead by the physician. An autopsy revealed cardiac hypertrophy and a narrowing of the aorta just distal to the ligamentum arteriosum, with dilation of the intercostal artery's ostia. How could the death have possibly been prevented?



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