Low blood sugar, or hypoglycemia, in diabetics who take medications such as insulin or oral diabetes pills is one of the causes of night sweating, states WebMD. Nighttime hypoglycemia typically occurs in diabetics who are very active during the day or who exercise before bedtime, as their blood glucose decreases, leading to a hypoglycemic reaction while sleeping, explains Joslin Diabetes Center.
Another factor that increases the risk of low blood glucose levels is alcohol consumption in the evening, which prompts the liver to clear the alcohol from the blood rather than produce glucose, states Joslin Diabetes Center. Diabetics who are taking fast-acting insulin also sometimes forget that the insulin takes effect for up to six hours. When they eat dinner late at night and sleep a few hours later, their blood glucose levels remain normal before bedtime. Nonetheless, their sugar levels tend to drop during sleep, because the insulin they took before dinner still acts in their bodies.
Sweating that causes diabetics to wake up with moist clothes and sheets, nightmares and a headache after waking up are common symptoms of nighttime hypoglycemia, notes Joslin Diabetes Center. To prevent low blood sugar levels at night, diabetics should check if their sugar levels are at least 140 milligrams per deciliter before bedtime. They should eat a snack before sleeping if they experience hypoglycemia symptoms, such as anxiety and a rapid heartbeat.