Synthetic opioids: increasingly seen in high-risk opioid use
While heroin remains the most commonly used illicit opioid, a number of sources suggest that licit synthetic opioids (such as methadone, buprenorphine, fentanyl) are increasingly misused. In 2015, 17 European countries reported that more than 10 % of all opioid clients entering specialised services presented for problems primarily related to opioids other than heroin. Opioids reported by treatment entrants include methadone, buprenorphine, fentanyl, codeine, morphine, tramadol and oxycodone. In some countries, non-heroin opioids represent the most common form of opioid use among treatment entrants. In Estonia, the majority of treatment entrants reporting an opioid as their primary drug were using fentanyl, while buprenorphine is the most frequently misused opioid in Finland. In the Czech Republic, although heroin is the most common primary opioid, other opioids account for just over half of those entering treatment for opioid-related problems.