My Blood Sugar Is Over 300 What Should I Do?

My Blood Sugar Is Over 300 What Should I Do? Experiencing a blood sugar reading over 300 mg/dL can feel overwhelming. You might wonder whether to panic, call for help, or simply ride it out. High blood sugar also known as hyperglycaemia can lead to severe complications if not addressed promptly.

This in-depth guide will walk you, step by step, through immediate actions, monitoring techniques, lifestyle adjustments, and long-term strategies to bring your levels back to a safe range. You’ll also find clear explanations of underlying causes and practical advice on preventing future spikes.

1. What Is Hyperglycaemia?

When blood glucose rises above normal, your body struggles to use or store sugar effectively. Glucose is your primary energy source, and insulin a hormone produced by your pancreas helps shuttle glucose into cells. If insulin is insufficient or cells resist its effects, glucose accumulates in your bloodstream.

• Normal ranges
  • Fasting (no food for 8 hours): 70–100 mg/dL
  • Pre-meal for people with diabetes: 80–130 mg/dL
  • Post-meal (1–2 hours after eating): < 180 mg/dL
• Hyperglycaemia threshold
  • Readings consistently above 180 mg/dL indicate elevated sugar.
  • A reading over 300 mg/dL requires immediate attention to prevent dehydration and serious complications.

Why 300 mg/dL matters?
At levels above 300 mg/dL, your kidneys try to remove excess sugar by producing more urine. This fluid loss can quickly lead to dehydration, which further concentrates blood sugar and disrupts electrolyte balance. Over time, persistent high readings increase your risk of damage to blood vessels, nerves, kidneys, eyes and heart.

2. Immediate Actions to Lower Your Reading

When you see a result above 300 mg/dL, focus on three priorities: confirm accuracy, rehydrate safely and, if appropriate, correct with medication.

2.1 Confirm Your Reading

1. Wash your hands thoroughly to avoid sugar residue skewing results.
2. Use a calibrated meter with fresh test strips.
3. Retest after two minutes. If your second reading remains high, assume it’s accurate.

2.2 Rehydrate

• Aim for water first: Drink 250–500 mL (one to two cups) of plain water immediately.
• Continue sipping: Over the next two to three hours, aim for at least 1–2 litres, unless your doctor restricts fluids.
• Avoid sugary or caffeinated drinks: These can worsen dehydration or further raise glucose.

2.3 Check for Ketones

If you have type 1 diabetes or a history of diabetic ketoacidosis (DKA), test for ketones at glucose levels over 300 mg/dL.

• Use urine strips or a blood ketone meter.
• Small/negative ketones let you manage at home.
• Moderate to large ketones demand immediate medical attention: call your doctor or attend A&E without delay.

2.4 Administer Corrective Insulin

For those on insulin therapy:

1. Know your correction factor (insulin sensitivity). Example: 1 unit lowers blood sugar by 50 mg/dL.
2. Calculate: (Current BG – Target BG) ÷ Correction factor = Units needed.
   • E.g., (300 – 120) ÷ 50 ≈ 3.6 → round to 4 units of rapid-acting insulin.
3. Inject carefully and log the dose.
4. Retest in 2 hours. If levels remain above 200 mg/dL, repeat the correction—up to your healthcare team’s recommended limit.

2.5 Avoid Vigorous Exercise Immediately

High-intensity workouts can trigger stress hormones that temporarily raise blood glucose, especially if ketones are present. Once levels drop below 250 mg/dL and no ketones are detected, a gentle 10–15 minute walk can help your body absorb glucose.

2.6 When to Seek Help

Call your doctor or emergency services if:

• Corrective insulin fails to reduce levels within 2–3 hours.
• Moderate or large ketones appear.
• You develop nausea, vomiting, severe abdominal pain, confusion, rapid breathing or signs of dehydration (dry mouth, sunken eyes, dark urine).

3. Logging and Monitoring

Detailed records help you and your healthcare team spot patterns and make informed adjustments.

Time	Blood Sugar (mg/dL)	Ketones	Insulin Dose	Fluid Intake	Notes (Food, Activity, Stress)
07:30	312	Small	4 units	300 mL water	Thirsty, headache
10:00	280	Negative	—	250 mL water	Breakfast: 2 slices whole-grain toast + egg
13:00	260	Negative	2 units	400 mL water	Walked 10 min
18:00	190	Negative	—	500 mL water	Lunch: grilled chicken salad, olive oil dressing
21:00	145	Negative	—	200 mL water	Light snack: 1 apple

Tips for effective logging

• Record every finger-stick reading, insulin dose, meal and exercise session.
• Note stress levels or illness, which can raise glucose.
• Review logs weekly with your healthcare team to refine targets and medication.

4. Long-Term Lifestyle Strategies

Keeping blood sugar under control isn’t just about reacting to spikes—it’s about preventing them.

4.1 Balanced Nutrition

1. Carbohydrate control
   • Count carbs at each meal. Aim for consistency day to day.
   • Tools: Smartphone apps like MyFitnessPal or Carb Manager.
2. Choose low-GI foods
   • Whole grains (oats, quinoa), legumes, non-starchy vegetables.
   • High-GI foods (white bread, refined sugars) cause rapid spikes.
3. Plate method
   • Half plate: non-starchy vegetables.
   • Quarter plate: lean protein.
   • Quarter plate: whole grains or starchy vegetables.
4. Mindful eating
   • Eat slowly, put utensils down between bites, and stop when 80 percent full.

4.2 Regular Physical Activity

• Aerobic exercise: 150 minutes per week of moderate-intensity (brisk walking, swimming, cycling).
• Resistance training: Two sessions per week (weights, resistance bands, bodyweight exercises).
• Post-meal walks: 10–15 minutes after meals can reduce post-prandial spikes up to 20 percent.

4.3 Weight Management

• Even 5–10 percent weight loss can improve insulin sensitivity significantly.
• Focus on small, realistic goals—lose 0.5–1 kg per week.

4.4 Stress Management

• Mind-body techniques: Deep breathing, progressive muscle relaxation, guided imagery.
• Mindfulness meditation: Apps like Headspace and Calm.
• Social support: Online or local diabetes support groups.

4.5 Sleep Hygiene

• Aim for 7–9 hours nightly.
• Poor sleep raises cortisol, which can increase insulin resistance.
• Strategies: consistent bedtime, cool dark room, limit screens 1 hour before sleep.

5. Medication Review and Adjustment

Work closely with your healthcare team to keep your regimen optimal.

5.1 Oral Antidiabetic Agents

• Metformin: First-line for many with type 2 diabetes. Reduces liver glucose output.
• Sulfonylureas (glipizide, glyburide): Stimulate insulin secretion. Risk low blood sugar.
• DPP-4 inhibitors (sitagliptin): Increase incretin hormones to boost insulin and lower glucagon.
• SGLT2 inhibitors (empagliflozin): Flush glucose via kidneys. Can lower blood pressure and weight.
• GLP-1 receptor agonists (liraglutide, semaglutide): Slow gastric emptying and increase satiety.

5.2 Insulin Therapies

• Basal insulin: Long-acting (glargine, detemir) covers background needs.
• Bolus insulin: Rapid-acting (lispro, aspart) with meals.
• Premixed insulin: Fixed ratio of basal and bolus for simpler dosing.
• Insulin pumps: Continuous subcutaneous infusion for precise control.

5.3 Continuous Glucose Monitoring (CGM)

• Provides glucose readings every 5–15 minutes, trend arrows and alarms.
• Helps identify patterns of highs and lows.
• Data reports guide fine-tuning of dosages and lifestyle.

5.4 Regular Medical Reviews

• HbA1c every 3–6 months to assess average control.
• Kidney function tests (eGFR, microalbuminuria).
• Lipid panel for cardiovascular risk.
• Eye exams and foot exams yearly.

6. Recognising and Treating Emergencies

Even with careful management, emergencies can occur.

6.1 Diabetic Ketoacidosis (DKA)

• Mostly in type 1 diabetes, but can affect type 2 during stress (infection, surgery).
• Symptoms: Thirst, frequent urination, nausea, vomiting, abdominal pain, fruity breath, rapid breathing, confusion.
• Cause: Insufficient insulin leads cells to burn fat: ketones build up, blood becomes acidic.
• Action: Call emergency services. Treatment: IV fluids, insulin infusion, electrolyte replacement.

6.2 Hyperosmolar Hyperglycaemic State (HHS)

• Type 2 diabetes under extreme dehydration and high stress.
• Blood sugar often > 600 mg/dL, minimal ketones.
• Symptoms: Severe dehydration, high fever, confusion, seizures.
• Action: Emergency admission for aggressive IV fluids, insulin, and monitoring.

7. Preventing Future Spikes

1. Structured Meal Plans
   • Plan weekly menus.
   • Prep balanced meals and snacks to avoid last-minute high-carb temptations.
2. Scheduled Exercise
   • Treat workouts like appointments.
   • Mix cardio with strength training for best insulin sensitivity.
3. Routine Monitoring
   • Set phone reminders for finger-sticks or CGM checks.
   • Use logs to detect dawn phenomenon (early-morning rise) or reactive hypoglycaemia.
4. Education and Support
   • Attend diabetes self-management programmes.
   • Keep up-to-date with guidelines from Diabetes UK or American Diabetes Association.
5. Technology Aids
   • Apps for carb counting, insulin calculators, reminders.
   • Smart insulin pens that track doses.

8. Psychological Wellbeing

Living with diabetes can strain mental health. Stress and anxiety can themselves spike blood sugar.

• Acknowledge emotions: It’s normal to feel frustrated, overwhelmed or scared.
• Seek counselling: Cognitive behavioural therapy helps manage health-related anxiety.
• Peer support: Sharing experiences with others in forums or local groups can reduce feelings of isolation.

9. Special Considerations

9.1 Illness and Infection

• Sickness often raises blood sugar via stress hormones.
• Sick-day rules:
  • Continue insulin or meds even if eating less.
  • Sip clear liquids frequently.
  • Test blood glucose and ketones every 2–4 hours.
  • Contact your doctor early.

9.2 Travel

• Pack extra medication, snacks, ketone strips.
• Adjust for time zone changes.
• Keep emergency contacts and doctor’s details accessible.

9.3 Alcohol and Social Occasions

• Alcohol can cause delayed low blood sugar, but sugary mixers spike first.
• Strategy: Limit to one drink, choose dry wines or spirits with sugar-free mixers, monitor levels closely.

10. Frequently Asked Questions

Must Read:

• How to Naturally Lower Blood Sugar Level in 30 Days Without Medication?
• Community Program Public Health Intervention Diabetes
• Why Controlling Blood Sugar Is Crucial for Your Health?

11. Case Study: Emma’s Turnaround

• Background: Emma, 45, type 2 diabetes for 10 years, struggled with post-meal spikes around 300–350 mg/dL.
• Challenges: Skipped breakfast, high-carb lunches at work, little exercise.
• Actions:
  • Began carb-counting with an app.
  • Replaced refined grains with whole grains.
  • Introduced 15 minutes of walking after each meal.
  • Set phone reminders to test glucose and take medication on time.
• Results (3 months later):
  • Fasting levels averaged 110 mg/dL (previously 140–160 mg/dL).
  • Post-prandial peaks stayed under 180 mg/dL.
  • Weight down by 5 kg, HbA1c from 8.2% to 7.1%.

12. Resources and Tools

• Apps:
  • MyFitnessPal (carb tracking)
  • Glucose Buddy (logging and trends)
  • Headspace (stress management)
• Websites:
  • Diabetes UK (guidelines, recipes)
  • American Diabetes Association (research updates)
• Local support:
  • Diabetes education classes at hospitals
  • Community health centres offering dietitian consultations

13. Conclusion:

A blood sugar reading over 300 mg/dL is a clear signal to act immediately. By confirming accuracy, rehydrating, testing for ketones and taking corrective insulin when needed, you can often bring levels back to a safer range at home. However, be prepared to seek medical help if symptoms worsen or corrective measures fail.

Long-term success rests on informed lifestyle changes—balanced nutrition, regular exercise, stress management, and proper sleep. Combined with routine monitoring, medication adherence and support from your healthcare team, these strategies help prevent future spikes and protect your health.

You’re not alone in this journey. Lean on technology, education programmes and support networks. With proactive management, you can keep your blood sugar within target ranges, reduce complications and enjoy a full, active life.