Signs of Low Blood Sugar and Type 2 Diabetes

Young worried businesswoman

Low blood sugar (hypoglycemia) is not just a concern for people with type 1 diabetes. Although it does not happen as often, people with type 2 diabetes also can be at risk and should be familiar with the signs of low blood sugar.

Blood sugar levels are considered too low when they drop below 70 mg/dL. Sometimes, people can experience symptoms at higher blood sugar levels, especially if their blood sugars have been elevated for an extended period of time.

When blood sugars drop below 70 mg/dL, the body may not have enough blood sugar (glucose) to provide for energy needs. If symptoms become severe without treatment or correction, low blood sugar levels can cause harm or even death. Knowing the signs and how to treat low blood sugar can help you avoid emergencies.

Increased Risks and Causes

Children, Older Adults, and Those With Hypoglycemia Unawareness

Those at higher risk for hypoglycemia include children, older adults, and those people who cannot identify low blood sugars—a term referred to as hypoglycemia unawareness. Hypoglycemia unawareness can occur if you are someone who experiences low blood sugars frequently. The frequency of low blood sugar can make the body desensitized to symptoms.The inability to feel symptoms, such as sweating, shaking, increased heart beat, anxiety or hunger, can make you incapable of treating the low which can result in unconsciousness or even death.

Therefore, it's important to know if you are at risk so that you can prevent and treat low blood sugars quickly and safely. 

Certain Medications:

People taking certain medications for type 2 diabetes, such as sulfonylureas, insulin, or a combination of insulin and non-insulin injectables. Some pill combinations and certain non-diabetes medications can also increase the risk for low blood sugar.

Ask your healthcare team about timing and dosing of medications and get educated so that you do not make an error in dosing. Be careful not to take too much medication and try to keep to a scheduled meal regimen. 

Other Causes: 

Excess alcohol consumption can also cause low blood sugar. Additionally, other causes include too much exercise without enough food to cover energy needs, skipping meals, small meals, kidney problems, and medical conditions such as hypothyroidism and Addison's disease.

Signs of Low Blood Sugar

Mild Symptoms

  • Blood sugar below 70 mg/dL
  • Perspiration
  • Shaking, trembling or feeling nervous
  • Mouth or lips tingling, tongue numbness, or metallic taste
  • Numbness or tingling of fingertips
  • Hunger
  • Rapid heartbeat
  • Weakness
  • Drowsiness
  • Confusion or inability to pay attention
  • Difficulty speaking
  • Mood changes such as aggressiveness, anxiety, irritability or tearfulness
  • Dizziness, headache or blurred vision
  • Clumsiness, jerkiness, and coordination problems
  • Difficulty walking
  • Paleness

Clinically Significant Symptoms

  • Blood sugar below 54mg/dL
  • Low body temperature
  • Convulsions or seizures
  • Loss of consciousness or coma
  • Loss of consciousness will require a glucagon injection or emergency medical treatment. Let friends and family know not to administer fluids, foods, or insulin if you lose consciousness. Educate friends and family about the signs of hypoglycemia, how to give a glucagon injection, and when to call 911.
  • If you are prone to low blood sugar make sure you are always wearing some sort of medical identification

Note: If low blood sugar occurs during sleep, you may experience nightmares, night sweats, irritability, confusion and feeling tired upon waking, or rebound hyperglycemia. 


If you are feeling any of the above symptoms, test your blood sugar. If it is below 70 mg/dL, follow the Rule of 15:

  • Eat 15 grams of fast-acting carbohydrates.
  • Wait 15 minutes and test blood sugar again.
  • Repeat until blood sugar is within normal range.
  • Eat a 15-30 gram carbohydrate snack that contains fiber and protein if you will not eat a meal within an hour.

    People who are taking acarbose (Precose) or miglitol (Gyset) should treat with pure glucose or dextrose, which comes as a tablet or gel. These medications slow digestion and other fast-acting carbohydrates may not be absorbed fast enough.


    If you are at high risk for hypoglycemia:

    • Monitor blood sugar levels frequently, especially before driving, before and after exercise, and before and after sex. If your levels are below 100 mg/dL before activity, eat a snack.
    • Follow your prescribed treatment and meal plan. Try not to skip meals or snacks.
    • Keep fast-acting carbs handy.
    • If you choose to drink alcohol, ask your health care team how to fit alcohol into your meal plan. If you drink an alcoholic beverage, drink it with a meal or snack.
    • Educate friends and family about the symptoms of low blood sugar and treatment.


    American Diabetes Association. Standards of Medical Care in Diabetes – 2017. Diabetes Care. 2017 Jan; 40 (Suppl 1): S1-132. 

    Hypoglycemia. National Diabetes Clearinghouse.

    Hypoglycemia. Pub Med Health. National Institutes of Health.

    Living with Diabetes. American Diabetes Association.