Thousands of teenagers in Syria have witnessed war and death first-hand, but even trying to stay alive can leave lasting damage to their mental health.

BBC Arabic went to Beirut to meet Mohamed, who briefly followed so-called Islamic State. His name, face and voice have been changed for his safety.

Produced by: Joelle Naayem, Eloise Dicker, Dina Demrdash

Illustrations: Jonathan Blezard