Hyperglycemia is the term that refers to an abnormally high level of sugar, or glucose, in the blood. Diabetes mellitus types 1 and 2 are by far the most common causes of hyperglycemia. In patients with either type 1 or type 2 diabetes, metabolic abnormalities lead to an elevation in blood glucose levels. When there is too much glucose in the blood, this can lead to a number of health risks and other symptoms. The main symptoms associated with hyperglycemia are
- increased thirst and
- frequent urination.
A severe elevation in blood glucose level can be life-threatening. This represents a medical emergency like diabetic ketoacidosis (DKA) or hyperglycemic hyperosmolar nonketotic syndrome (HHNS, also referred to as hyperglycemic hyperosmolar state). Some symptoms of hyperglycemia occur when the hyperglycemia is present for a long time, such as poor wound healing and weight loss. In emergencies like diabetic ketoacidosis, symptoms include nausea, vomiting, abdominal pain, confusion, shortness of breath, and a fruity odor to the breath.
Causes of hyperglycemia
Type 1 or type 2 diabetes is the most common cause of hyperglycemia. Other causes can include pancreatitis, Cushing's syndrome, unusual hormone-secreting tumors, pancreatic cancer, certain medications, and severe illnesses.
Other high blood sugar symptoms and signs
- Abdominal Pain
- Blurred Vision
- Breath That Smells Fruity
- Confusion
- Dehydration
- Dry Mouth
- Fatigue
- Frequent Urination
- Headache
- Hunger
- Increased Thirst
- Nausea
- Poor Wound Healing
- Shortness of Breath
- Tiredness
- Trouble Concentrating
- Vomiting
- Weakness
- Weight Loss
Main Article on High Blood Sugar Symptoms and Signs

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Examples of Medications for High Blood Sugar Symptoms and Signs
- Actos (pioglitazone)
- Amaryl (glimepiride)
- exenatide (Byetta)
- factor VIII
- glipizide (Glipizide XL, Glucotrol)
- metformin
- mifepristone
- miglitol, Glyset
- Mounjaro (tirzepatide)
- Precose (acarbose)
- repaglinide (Prandin)
- rosiglitazone (Avandia)
- sitagliptin (Januvia)
- Starlix (nateglinide)
- stevia
- Tradjenta (linagliptin)
- Trulicity (dulaglutide)
- Types of Insulin Medications for Diabetes
- Victoza (liraglutide)
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