Flower Mound police spotted what they thought was an intoxicated driver and were initiating a pursuit on FM 2499 when the vehicle drifted to the side of the road and flipped, police said.
When officers made contact with the driver, it became apparent he was having a medical emergency.
According to police, the situation is a fairly common occurrence with diabetics, which they believe was the case in the incident which occurred earlier this afternoon.
Police say the man is getting appropriate medical attention at this time, though his current status is not known.