with varying findings. A 2013 national survey indicated that 74% of people who recreationally use opioids acquired their opioids directly from a single doctor, friend, or relative who received their opioids from a clinician. Among pharmacies, the most prolific distributor was Walgreens, which bought 13 billion oxycodone and hydrocodone pills from 2006 through 2012 (about twenty percent of all such pills in US pharmacies). Though aggressive opioid prescription practices played the biggest role in creating the epidemic, the popularity of illegal substances such as potent heroin and illicit fentanyl has become an increasingly large factor. It has been suggested that decreased supply of prescription opioids caused by opioid prescribing reforms directed people who were already addicted to opioids to illegal substances. In 2015, approximately 50% of drug overdoses were not the result of an opioid product from a prescription, though most recreational users' first exposure had still been by lawful prescription. By 2018, another study suggested that 75% of people who use opioids recreationally started their opioid use by taking drugs obtained in a way other than by legitimate prescription. History Opiates such as morphine have been used for pain relief in the United States since the 1800s, and were used during the American Civil War. Opiates soon became known as a wonder drug and were prescribed for a wide array of ailments, even for relatively minor treatments such as cough relief. Bayer began marketing heroin commercially in 1898. Beginning around 1920, however, the addictiveness was recognized, and doctors became reluctant to prescribe opiates. Heroin was made an illegal drug with the Anti-Heroin Act of 1924, in which the US Congress banned the sale, importation, or manufacture of heroin. In the 1950s heroin addiction was still fairly uncommon among average Americans, many of whom saw it as a frightening condition. The fear extended into the 1960s and 1970s, although it became common to hear or read about drugs such as cannabis and psychedelics, which were widely used at rock concerts like Woodstock. Heroin addiction began to make the news around 1970 when rock star Janis Joplin died from an overdose. During and after the Vietnam War, addicted soldiers returned from Vietnam, where heroin was easily bought. Heroin addiction grew within low-income housing projects during the same time period. In 1971, congressmen released an explosive report on the growing heroin epidemic among US servicemen in Vietnam, finding that ten to fifteen