The High-Sugar Alert: 12 Signs Your Blood Sugar May Be Too High

High blood sugar (hyperglycaemia) can occur in people with diabetes, prediabetes, or, less commonly, other medical conditions. A single symptom does not mean you have high blood sugar, but several symptoms together warrant medical evaluation.

1. Frequent Urination

High blood sugar causes the kidneys to remove excess glucose through urine, leading to more frequent trips to the toilet, especially at night.

2. Excessive Thirst

Losing more fluid in urine can make you feel unusually thirsty, even if you’re drinking plenty of water.

3. Increased Hunger

Despite high blood sugar, your body’s cells may not be getting enough glucose to use for energy, leading to increased hunger.

4. Fatigue

Feeling unusually tired or lacking energy is a common symptom of persistently elevated blood sugar.

5. Blurred Vision

High blood sugar can temporarily change the shape of the eye’s lens, causing blurred vision. Persistent or sudden vision changes should always be assessed by a healthcare professional.

6. Slow-Healing Cuts or Sores

High blood sugar can impair the body’s ability to heal wounds and fight infection.

7. Frequent Infections

People with poorly controlled diabetes may experience more:

• Urinary tract infections
• Skin infections
• Yeast infections

8. Unexplained Weight Loss

This is more common in untreated diabetes, particularly Type 1 diabetes, when the body starts breaking down fat and muscle for energy.

9. Tingling or Numbness

Long-term high blood sugar can damage nerves, causing:

• Pins and needles
• Burning sensations
• Numbness, especially in the feet and hands

10. Dry Mouth

Frequent urination can lead to dehydration, resulting in a dry mouth and lips.

11. Itchy or Dry Skin

Dehydration and reduced circulation may contribute to dry, itchy skin.

12. Fruity-Smelling Breath (Medical Emergency)

A fruity or sweet-smelling breath, especially when accompanied by:

• Nausea or vomiting
• Deep or rapid breathing
• Severe abdominal pain
• Confusion

may be a sign of diabetic ketoacidosis (DKA), a life-threatening complication that requires immediate emergency medical care.

Who Is at Higher Risk?

Risk factors for diabetes include:

• A family history of diabetes
• Being overweight or obese
• Physical inactivity
• High blood pressure
• High cholesterol
• A history of gestational diabetes
• Increasing age

How Is High Blood Sugar Diagnosed?

A healthcare professional may recommend:

• A fasting blood glucose test
• An HbA1c blood test, which reflects average blood sugar over the previous 2–3 months
• An oral glucose tolerance test in certain situations

When to Seek Medical Attention

Arrange a medical appointment if you have persistent symptoms of high blood sugar.

Seek emergency care immediately if you have:

• Fruity-smelling breath
• Severe vomiting
• Confusion
• Difficulty breathing
• Extreme drowsiness or difficulty staying awake

These can be signs of diabetic ketoacidosis or another serious medical condition.