Hypoglycemia: Symptoms, Causes, and What to Do Immediately

Hypoglycemia — low blood sugar — is the most frequent metabolic emergency in diabetics undergoing therapy. It can be frightening the first time, but it's manageable if you know what to do and have your glucometer handy.

What is Hypoglycemia

Hypoglycemia is defined as blood sugar dropping below 70 mg/dL (3.9 mmol/L). It is classified into three degrees of severity:

Symptoms of Hypoglycemia

Symptoms are divided into two categories:

Adrenergic Symptoms (first to appear)

• Hand tremors
• Sudden cold sweats
• Palpitations and accelerated heartbeat
• Pallor
• Sudden hunger
• Anxiety and irritability

Neuroglycopenic Symptoms (lower blood sugar — the brain lacks glucose)

• Mental confusion, difficulty concentrating
• Blurred or double vision
• Headache
• Strange or aggressive behavior (often noticed by those nearby)
• Difficulty speaking
• In severe cases: loss of consciousness, seizures

Beware of hypoglycemia unawareness: people who have had many episodes of hypoglycemia over time may lose the ability to detect early adrenergic symptoms. In these cases, frequent monitoring — or CGM — is essential.

Causes of Hypoglycemia

In Diabetics on Therapy (most common causes)

• Insulin dose too high relative to the meal consumed
• Meal skipped or delayed after taking medication
• Unplanned physical activity (consumes extra glucose)
• Alcohol on an empty stomach (blocks liver glucose production)
• Error in the dose of secretagogue drugs (sulfonylureas, glinides)

In Non-Diabetics

• Prolonged fasting or very restrictive diets
• Intense physical activity without adequate nutrition
• Postprandial reactive hypoglycemia (2–4h after meals rich in high GI carbohydrates)
• Use of certain medications (high-dose aspirin, beta-blockers, quinolones)
• Rare conditions: insulinoma, adrenal insufficiency, severe malnutrition

What to Do: The Rule of 15-15

The 15-15 rule is the standard protocol for treating mild-to-moderate hypoglycemia (blood sugar 40–70 mg/dL with a conscious patient):

1. Take 15g of fast-acting carbohydrates (see list below)
2. Wait 15 minutes without eating anything else
3. Measure blood sugar again
4. If it is still below 70 mg/dL: repeat the cycle (another 15g + 15 minutes)
5. When blood sugar is above 70 mg/dL: eat a small protein snack to stabilize it (crackers + cheese, or dried fruit)

15 grams of fast carbs are equivalent to:

• 3–4 glucose tablets (always carry them with you)
• 150 mL of fruit juice or sugary drink (not diet)
• 1 tablespoon of sugar or honey dissolved in water
• 100 mL of Coca-Cola or similar (not zero)

What NOT to do: do not eat chocolate, ice cream, or fatty foods — fat slows down carbohydrate absorption and blood sugar rises slowly. Do not eat "until you feel better" — you risk overshooting.

Severe Hypoglycemia: Glucagon and Emergency Room

If the person is unconscious or unable to swallow: DO NOT attempt to give them anything to drink — risk of choking.

• Place them on their side (recovery position)
• Administer intramuscular glucagon if available (prescription kit for diabetics on insulin therapy)
• Call 118 immediately

Prevention: How to Avoid Hypoglycemia

• Measure blood sugar before and after intense physical activity
• Do not skip meals after taking secretagogue drugs or insulin
• Always carry glucose or fruit juice with you
• Inform family members or colleagues that you are diabetic and where you keep emergency glucagon
• Set a low blood sugar alarm on the app if you use a glucometer with Bluetooth

The VitaeChek G1 Pro with the integrated app allows you to set personalized alarm thresholds: when blood sugar drops below your chosen threshold (e.g., 80 mg/dL), the app sends a notification — a useful reminder to act before the situation becomes critical.

Frequently Asked Questions

Blood sugar 65 without symptoms: should I treat it?

Yes. Even if you don't feel symptoms, blood sugar below 70 mg/dL requires the 15-15 rule. The absence of symptoms may indicate hypoglycemia unawareness — a condition that requires discussion with your diabetologist.

Does hypoglycemia cause diabetes?

No. Hypoglycemia does not cause diabetes. In non-diabetics, recurrent hypoglycemic episodes may indicate conditions that warrant medical evaluation.

Can I drive with low blood sugar?

No. Never drive if your blood sugar is below 90 mg/dL. Before driving, always measure your blood sugar and treat any low values before setting off.