Which organ is the first affected during hypoglycemia?

• A. Liver
• B. Brain
• C. Muscle
• D. Pancreas

Answer: (B)

Glucose is the brain’s main fuel and neurons have little in the way of energy reserves. When blood glucose falls, neuronal energy production drops quickly, leading to neuroglycopenia. That rapid energy shortage causes early mental and neurological symptoms—confusion, dizziness, impaired judgment, and even seizures or loss of consciousness if it worsens. The liver’s role is to raise blood glucose by releasing stored glucose, but that is a response mechanism rather than a tissue that becomes impaired first. Muscles can also use other fuels and tolerate low glucose longer, and the pancreas mainly hormonally responds to hypoglycemia rather than showing immediate functional failure. Therefore, the brain is the first organ affected during hypoglycemia.