Glucose · low result
What does a low Glucose mean?
Short answer
A low glucose (hypoglycemia, generally below 70 mg/dL) in someone not taking diabetes medication is uncommon and worth explaining. Prolonged fasting, alcohol, intense exercise, certain medications, adrenal or liver problems, and rarely an insulin-producing tumor cause it. In someone on insulin or sulfonylureas it's usually a medication effect. A sample left unspun for hours also reads falsely low.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
When does this result need same-day care?
- Low glucose with confusion, seizure or loss of consciousness — emergency care
What is the normal range for Glucose?
- age 18+, fasting: 70.0 – 99.0 mg/dL
Can reflect prolonged fasting, certain medications (especially diabetes drugs), or hormonal conditions.
Full reference table, citations and testing options: Glucose biomarker page.
What are the common causes of low Glucose?
- Diabetes medication (insulin, sulfonylureas) — the most common cause overall
- Prolonged fasting or heavy alcohol without food
- Post-bariatric surgery or reactive hypoglycemia after meals
- Adrenal insufficiency, liver disease, kidney failure
- Rare: insulinoma
- Lab artifact from delayed sample processing
What symptoms go with low Glucose?
- Shakiness, sweating, hunger, fast heartbeat
- Confusion, blurred vision, irritability
- Fainting or seizures when severe
What do clinicians usually check next?
- Repeat with prompt processing; a glucose meter log during symptoms
- Insulin and C-peptide drawn during a low episode if recurrent
- Morning cortisol, liver and kidney panels
- Medication review
Follow-up tests available at TestWell: Cortisol (AM) ($26.99), C-Peptide ($29.99), Cortisol ($32.99).
The ADA suggests re-screening at least every 3 years when fasting glucose is normal, and at least once a year with prediabetes (100–125 mg/dL). A single fasting result at or above 126 mg/dL is confirmed with a repeat test — or an A1c — before it counts as diabetes.
How do you recheck Glucose?
Prices are cash-pay; every order adds one $6 lab processing fee. Physician authorization is included; no insurance or referral needed.
| Test or panel | Type | Price | Fasting | Results |
|---|---|---|---|---|
| Basic Metabolic Panel | Test · 8 biomarkers | $20.99 | Yes | 1–3 business days |
Common questions
My fasting glucose was 65 and I feel fine. Is that a problem?
Probably not — healthy people, especially after a long overnight fast or exercise, can run in the 60s without symptoms. Recurrent readings below 60, or any with symptoms, should be evaluated.
Educational content, not a diagnosis. Lab results are one input; a clinician interprets them with your history and exam.