How do i keep my sugar levels from crashing?

Answer by Dr. Albana Greca Sejdini, MD, MMedSc

Medically reviewed by Dr. Ruden Cakoni, MD, Endocrinologist | Last reviewed: July 2026

Hi Wiley,

A reading of 220 mg/dL is not a normal after-meal target. For many nonpregnant adults with diabetes, the usual goal is below 180 mg/dL about 1–2 hours after the start of a meal. A reading taken immediately after eating is harder to interpret, so record the exact testing time and compare it with this guide to blood sugar levels after eating.

A fasting home reading of 125 mg/dL also needs proper follow-up. A laboratory fasting plasma glucose of 100–125 mg/dL is in the prediabetes range, while 126 mg/dL or higher may indicate diabetes if confirmed. A home glucose meter cannot diagnose diabetes, so ask for laboratory fasting glucose and an HbA1c test.

First, Confirm That the Drop Is Real

Food or sugar on the fingers, damaged strips, testing technique, and meter variation can produce misleading results. The next time this happens:

1. Stop what you are doing and sit somewhere safe. Do not drive.


2. Wash your hands with soap and water and dry them completely.


3. Repeat the test immediately with a new strip, preferably from another finger.


4. If you use a continuous glucose monitor, confirm an unexpected reading with a finger-stick meter because CGM readings can lag behind blood glucose.


5. Record the meal, medicines, symptoms, and readings before eating and at 30, 60, and 120 minutes after the first bite. Do not keep testing every few minutes unless treating a confirmed low.

A true fall this rapid requires review, but it is not the typical timing of reactive hypoglycemia. Reactive hypoglycemia usually occurs within about four hours after eating and should be diagnosed only when low glucose is documented during symptoms and the symptoms improve when glucose returns to normal.

What to Do During an Episode

If your glucose is below 70 mg/dL and you are awake and able to swallow, take about 15 grams of fast-acting carbohydrate—such as glucose tablets or 4 ounces (120 mL) of juice. Recheck after 15 minutes and repeat if it is still below 70. Read the complete low blood sugar treatment guide.

If the reading is in the 70s, repeat it to confirm. Do not repeatedly consume large amounts of sugar unless the glucose is truly low or your clinician has given you a different plan; overtreatment can create another high-and-low cycle.

How to Reduce the Swings Until You Are Evaluated

• Avoid sugary drinks, sweets, or refined carbohydrates by themselves, especially on an empty stomach.


• Pair a controlled portion of high-fiber carbohydrate with protein and healthy fat—for example, whole-grain toast with egg, or plain yogurt with nuts.


• Choose smaller balanced meals if large meals trigger symptoms, but do not skip meals.


• Stay normally hydrated and limit alcohol, especially without food.


• Avoid strenuous exercise while dizzy or during a suspected glucose drop.


• Do not change insulin or diabetes tablets without the prescribing clinician.

Please arrange an appointment soon and take your glucose log and meter. Your clinician should review your medicines—especially insulin or sulfonylureas—meal timing, alcohol, activity, kidney and liver health, previous stomach surgery, and other possible causes. Appropriate testing may include laboratory fasting glucose, HbA1c, and sometimes short-term continuous glucose monitoring. Thyroid, hormone, or pancreatic testing should be ordered only when the history and confirmed glucose results suggest it.

The panic feeling may be triggered by the physical sensations of a rapid glucose change, but dizziness and severe headache should not automatically be blamed on anxiety. Confirm the glucose and let your clinician assess other possible causes.

Related Questions

• Why are my glucose levels between 30 and 50 mg/dL?


• Can low blood sugar cause altered behavior and confusion?


• Why is my morning blood sugar higher than my bedtime reading?

Related Resources

• Dangerous Blood Sugar Levels and Emergency Signs


• Blood Sugar Levels by Time of Day


• Common Causes of Low Blood Glucose


• Normal Blood Sugar Level Chart

References

• American Diabetes Association: Glycemic Goals, Hypoglycemia, and Hyperglycemic Crises—2026


• CDC: Treatment of Low Blood Sugar


• NIDDK: Diabetes and Prediabetes Tests


• FDA: Blood Glucose Monitoring Devices

Medical disclaimer: Educational only—not personal medical advice.