The objective of this article is to review how primary care providers - paediatricians, family practitioners, nurse practitioners - could address the use of substances by adolescents and respond to problematic behaviours and situations. Given the highly addictive properties of nicotine, adolescents should be supported in avoiding any consumption of tobacco or quitting if they already do so. Screening and investigation of substance use is usually not difficult, provided that it is processed in a neutral and empathetic atmosphere and securing confidentiality if the adolescent asks for it. Any type of substance use is potentially linked with adverse events such as injuries, violence, unplanned and unsafe sexual experience, alcoholic coma, 'bad trips' or unpleasant psychological experiences. As such, substance use should be identified and openly discussed with the adolescent. Moderate intermittent recreational use of legal and illegal substances (mainly alcohol and cannabis) should be carefully monitored over time, as it can lead to problematic use. Problematic use and substance use disorder require various interventions, including motivational interviewing, family counselling and psychotherapy, especially when substance use is linked with mental health disorders. Despite the importance of confidential care, parents or caregivers should be involved in problematic situations as much as possible. What is known: • While problematic use of substances is transient amongst many adolescents, it may be a threat to health and school/professional functioning • Primary care providers (PCPs) can address queries or offer preventive interventions to adolescents who use substances What is new: • Some interview tools can assist PCPs efficiently to identify problematic users of substances • There are effective approaches that PCPs can use to address problematic use by adolescent patients.