Absolutely. If you have diabetes, stress can increase your blood sugar. A severe psychological stress or any significant physical stress (such as a heart attack, burn, infection, pain or surgery) can raise the blood sugar. It does so by increasing the activity of two body hormones cortisol and epinephrine.
Cortisol is a hormone that is made by your adrenal glands, found above each kidney. Stress causes your brain to release the protein adrenocorticotropin hormone (ACTH). This hormone enters the bloodstream. Then it travels to the adrenal glands, instructing them to make larger amounts of cortisol.
Epinephrine, commonly known as adrenaline, is also made in the adrenal glands. Stress causes nerve endings in the adrenal glands to become active. This causes the release of this hormone into the blood as an adrenaline rush.
Your liver stores glucose. When there are higher levels of cortisol and epinephrine in the body, the liver releases glucose into the bloodstream. Also, these two hormones make glucose move out of the bloodstream less efficiently. Stress-related increases in blood sugar are most easily noticed after a stress that is severe. Mild chronic stress might also affect blood sugar control. But it has been harder for researchers to prove this relationship.