A person is unconscious for more than a few seconds.
Confusion occurs with other signs of a stroke, such as sudden weakness, numbness, inability to move, changes in vision, or slurred speech.
Confusion and memory loss develop quickly, over a few hours or days. This is called delirium. It can be a sign of many serious problems, such as a medicine problem, an infection, an alcohol or drug problem, or a worsening of a long-term illness like heart disease or diabetes.
Call a doctor if:
A person faints for a second or two and is now awake.
A person with diabetes faints, even if he or she is now awake. This could be a low or high blood sugar emergency.