Four fire engines and around 25 firefighters were called to a small fire at a hospital on Landor Road in Stockwell.
The fire was extinguished quickly but there was heavy smoke logging throughout the first floor. Around 45 people evacuated the building before the Brigade arrived.
The Brigade was called at 0906 and the fire was under control by 1041. Fire crews from Brixton and Lambeth fire stations were at the scene. The cause of fire is under investigation.