R40.2: Coma, unspecified

If a person is unconscious, they will be in an abnormal, sleep-like state. The person cannot even be woken up by strong stimuli such as pain. If a person is unconscious, they can no longer perceive themselves or their environment. The eyes are closed and the person is unable to react to prompts.

One may be unconscious if the brain is not functioning properly. For various reasons, the brain is no longer able to function properly. The brain may have been damaged. The brain can be damaged by injury, pathogens or other diseases, for example.

Patient Disclaimer

The information provided on this page is for general educational purposes only. It is not intended for self-diagnosis and does not replace professional medical advice. Always consult your doctor or a qualified healthcare provider with any questions or concerns about your health.

If you see an ICD diagnosis code (e.g., on a medical report), be aware that doctors may also include additional indicators to express diagnostic certainty. Only a healthcare professional can interpret these codes accurately in the context of your individual case.

For a complete understanding of your condition and what the diagnosis means for you, please speak directly with your doctor.