Four fire engines and 21 firefighters and officers were called to a fire at a residential care home in Kenilworth Road, Ealing.
Staff alerted the Brigade after a smoke alarm sounded. A small section of the ground floor was damaged by fire. A man was suffering from smoke inhalation and treated at the scene by London Ambulance Service crews. Three women were also assessed at the scene as a precaution.
The Brigade was called at 2332 and the fire was under control at 0036. Fire crews from Ealing, Acton, Chiswick, and Southall fire stations attended the scene.
The cause of the fire is under investigation by the Brigade and the Metropolitan Police Service.