Why do I always feel dizzy after donating blood?
Disease description:
I have donated blood several times this year, but I always feel dizzy after donating, and my whole body feels particularly weak afterward. I would like to know why dizziness occurs after blood donation.
Doctor's answer (1)
Dr. Liu Feng
Dizziness after blood donation may be caused by the following reasons:
1. Physiological factors: Some donors may experience dysfunction of the autonomic nervous system due to anxiety or fear, which can lead to dizziness. This condition usually does not require special treatment and can be relieved by rest and relaxation.
2. Reduced blood volume: During blood donation, the body loses about 400 mL of blood at once, resulting in a temporary reduction in blood volume, which can affect circulation and oxygen delivery, thereby causing dizziness.
3. Low blood sugar: Energy is consumed during the blood donation process. If the donor has not eaten or has eaten insufficiently prior to donation, it may lead to decreased blood glucose levels, causing symptoms such as dizziness and fatigue.
4. Other diseases: Insufficient cerebral blood supply, hypotension, and other factors may also cause dizziness after blood donation.
Donors should ensure adequate rest before donation and avoid donating on an empty stomach. After donation, it is important to rest and avoid strenuous activity. If dizziness persists or worsens, prompt medical attention is recommended.
