Cancer causes fatigue for a variety of reasons. The disease prompts a lot of changes within the body and can release certain substances that cause lethargy. Lung cancer also increases the amount of energy the body requires to function normally. To compensate for the cancerous lung tissue, the body works harder to maintain normal functioning, leaving people feeling drained.

This site offers information designed for educational purposes only. You should not rely on any information on this site as a substitute for professional medical advice, diagnosis, treatment, or as a substitute for, professional counseling care, advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a physician or other healthcare professional.