Letter C
Cyanosis
Also known as: Blue lips, Blue skin
Cyanosis symptom guide: what it can mean, possible causes, and when to seek care. Educational only.
Overview
Cyanosis is an emergency sign that the body is short of oxygen. It can follow lung, heart, or airway problems. Get help fast—do not wait for it to clear on its own.
Possible causes
- Severe breathing trouble / asthma
- Pneumonia or COVID-19
- Heart problems
- Airway blockage
- Extreme environmental cold
When to see a doctor
Call emergency care immediately for blue lips or nails, especially with breathing difficulty.