Family members affected by a relative's substance misuse looking for social support: who are they?

•The average time undertaken by affected family members (AFMs) to seek help after discovering about the relative substance use problem was 2.6 years.•It took an average of six years for 58% of this research population to seek support from the time their relative started to use substances.•A high percentage thought the substance use of their relatives was just a transient problem, or that they could cope with the problem by themselves.•A high percentage of care for AFMs provided by women and/or offspring.