High blood sugar in non-diabetic patients can be caused by a variety of factors. The most common are:
Polycystic ovarian syndrome: This condition leads to hormonal imbalances in women of reproductive age. This can lead to high production of testosterone, insulin and cytokines. Even they are insulin resistant and cannot use all the blood glucose to produce energy.
Stress: Uncontrolled stress can increase the levels of hormones like cortisol and adrenaline. They take turns raising blood sugar levels, which is a completely normal response to the emotional pain that a person is going through.
Infections: Any type of infection also increases the levels of the stress hormone cortisol. This hormone blocks the ability of insulin to remove excess glucose from the bloodstream, resulting in persistently high blood sugar levels.
Medications: Some drugs, such as dopamine and norepinephrine, immunosuppressants and corticosteroids, such as tacrolimus and cyclosporine, can activate blood enzymes that can keep blood sugar levels steadily rising. It becomes difficult to produce energy in the body and the person feels tired all the time.
Obesity: Excess of fat cells makes the body resistant to insulin. This makes it difficult to remove glucose from the blood and use it for energy production.