RT Book, Section A1 Phillips, Karran A. A1 Bonci, Antonello A2 Jameson, J. Larry A2 Fauci, Anthony S. A2 Kasper, Dennis L. A2 Hauser, Stephen L. A2 Longo, Dan L. A2 Loscalzo, Joseph SR Print(0) ID 1155960442 T1 Cocaine and Other Commonly Used Drugs T2 Harrison's Principles of Internal Medicine, 20e YR 2018 FD 2018 PB McGraw-Hill Education PP New York, NY SN 9781259644016 LK accesspharmacy.mhmedical.com/content.aspx?aid=1155960442 RD 2024/03/28 AB The use of cocaine and other psychostimulants reflects a complex interaction between the pharmacology of the drug, the personality and expectations of the user, and the environmental context in which the drug is used. Polydrug use involving the concurrent use of several drugs with different pharmacologic effects is increasingly common. Sometimes one drug is used to enhance the effects of another, as with the combined use of cocaine and nicotine, or cocaine and heroin in methadone-maintained patients. Some forms of polydrug use, such as the combined use of IV heroin and cocaine, are especially dangerous and account for many hospital emergency room visits. Chronic cocaine and psychostimulant use may cause a number of adverse health consequences and may exacerbate preexisting disorders such as hypertension and cardiac disease. In addition, the combined use of two or more drugs may accentuate medical complications associated with use of one drug. Chronic drug use is often associated with immune system dysfunction and increased vulnerability to infections, including risk for HIV infection. The concurrent use of cocaine and opiates (“speedball”) is frequently associated with needle sharing by people using drugs intravenously. People who use IV drugs represent the largest single group of individuals with HIV infection in several major metropolitan areas in the United States as well as in many parts of Europe and Asia.