Overview
Low blood sugar can become dangerous quickly.
Some people don't feel warning signs.
When to get medical care
Causes
Causes include diabetes medicines, skipped meals, and alcohol.
OwieClear has pages on 4 conditions that can cause low blood sugar. Each shows how soon to get care.
Common causes
- Low blood sugar (hypoglycemia)Often needs care today
Blood sugar that drops too low, most often in people taking insulin or some diabetes pills.
Less likely causes
- Multiple endocrine neoplasia (MEN1, MEN2)See a doctor if it doesn't get better
Inherited syndromes that cause tumors in several hormone glands.
- Pancreatic neuroendocrine tumor (islet cell tumor)See a doctor if it doesn't get better
A tumor of the hormone-making cells of the pancreas, different from the more common pancreatic cancer.
- Solitary fibrous tumorSee a doctor if it doesn't get better
A rare tumor that can grow almost anywhere, most often the lining of the lung, the belly, or the brain's lining.
What you can do at home
- Eat 15 grams of fast sugar, then recheck in 15 minutes.
- Follow with a snack.
Medicines
Diabetes medicines may need adjusting. Glucagon for severe lows.
At the doctor
Blood sugar testing.
Questions you may be asked
- Medicines
- Meals
The exam
A physical exam.
Tests
- Blood sugar
Prevention
Prevent lows.
- Eat regularly
- Check blood sugar
Check your symptoms
Most symptoms have more than one possible cause. The symptom checker looks at all of your symptoms together, plus your age, and shows how soon to get care.
Sources
Last updated 2026-11-13.