"Among first-time clients entering specialised drug treatment in 2021, or most recent year available, with heroin as their primary drug, 19% (down from 38% in 2013) reported injecting as their main route of administration. In this group, levels of injecting vary between countries, from less than 10% in Denmark, Spain, France and Portugal to 60% or more in Czechia, Estonia, Latvia, Lithuania, Romania and Slovakia."
Source
European Monitoring Centre for Drugs and Drug Addiction (2023), European Drug Report 2023: Trends and Developments, last accessed July 9, 2023.