Officers were called to an address in Mount Pleasant Road.
Paramedics were also sent to the scene.
A spokesman for Sussex Police said: “Emergency services were called to a medical emergency in Mount Pleasant Road, Hastings, at 3.10pm on August 17.
“A man was taken to the Royal Sussex County Hospital via air ambulance, for treatment to a self-inflicted injury.
“No offences have been identified.”
The air ambulance was seen landing in Alexandra Park at around 3.45pm yesterday.
A spokesman for South East Coast Ambulance Service said it landed to assist paramedics already at the scene of yesterday’s incident.