Nocturnal hypoglycemia refers to low blood glucose levels during sleeping. Regularly monitoring glucose levels and adjusting insulin dosages can help prevent nocturnal hypoglycemia.
Nocturnal hypoglycemia is a potential complication for individuals managing diabetes with glucose-lowering medications. It occurs when blood sugar (glucose) levels drop below suitable ranges during sleep.
Hypoglycemia occurs when blood sugar levels drop below a healthy threshold for a particular person. Typically, this is below 70 milligrams per deciliter (mg/dL). People may also refer to these occurrences as a “hypo” or a period of low blood sugar. It is more frequent in those who manage their diabetes with insulin.
Sometimes, a person may experience nocturnal hypoglycemia, where their blood sugar levels drop during the nighttime. These occurrences can disrupt sleep patterns, cause headaches, and can potentially be dangerous if an individual cannot wake up to treat their nighttime hypo.
This article looks at nocturnal hypoglycemia in more detail, including causes, symptoms, and how to manage and prevent them from occurring.
Nighttime hypos, or nocturnal hypoglycemia, refers to periods of low blood sugar levels during the night, typically while a person is sleeping.
Glucose levels naturally fluctuate during the night as part of the body’s circadian rhythm. However, for people living with diabetes, the complex interplay of insulin, diet, physical activity, and sleep can lead to extreme fluctuations, resulting in hypoglycemia.
Common symptoms a person may experience from nocturnal hypoglycemia include:
- sweating and waking up with damp clothes or sheets
- waking up with a headache
- feeling tired in the morning
- having nightmares
In some cases, a person may experience the Somogyi effect. This phenomenon refers to a rebound effect where, after experiencing nocturnal hypoglycemia, the body releases a surge of hormones, leading to high blood sugar levels when waking up in the morning.
Read on to learn more about the Somogyi effect.
Several factors may cause someone to experience nocturnal hypoglycemia.
- increasing physical activity beyond a person’s usual routine
- alcohol consumption
- overestimating insulin doses
- skipping dinner
- not consuming enough carbohydrates
A 2021 review also notes that the following factors may also increase the risk of nocturnal hypoglycemia:
- older age
- being female
- longer duration of diabetes
If a person wakes up due to experiencing nocturnal hypoglycemia, they need to treat their hypo as they would during the day. This typically involves consuming 15 grams of fast-acting carbohydrates.
Read on to learn more about treating hypoglycemic events and about the rule of 15.
Regular monitoring of glucose levels
Before going to bed, a person with diabetes should check their glucose levels. They can ask their diabetes healthcare team about suitable blood sugar targets before bed.
A 2021 review recommends using a continuous glucose monitoring (CGM) system to track glucose levels.
Having a bedtime snack
Consuming a small, balanced snack before bed can help prevent overnight drops in blood sugar. For example, suitable snacks include a small piece of fruit and some nuts or a small slice of wholegrain bread and peanut butter. A person can discuss if they should have a snack and suitable snack options with their healthcare team.
Timing exercise
If a person engages in physical activity, it may be advisable to try and schedule it earlier in the day to minimize the risk of nocturnal hypoglycemia.
Medication management
A person can work closely with a healthcare professional to adjust insulin dosages or other medications as necessary. By ensuring they do not administer too large a dose before bed, individuals can help prevent nocturnal hypoglycemia.
Limit alcohol consumption
It is advisable to limit alcohol consumption, especially close to bedtime. If a person living with diabetes chooses to drink, they need to consider having some carbohydrates before bed.
In most cases, nocturnal hypoglycemia is manageable with certain lifestyle and regimen adjustments. A person needs to contact their diabetes care team if they are experiencing regular episodes of nocturnal hypoglycemia.
If someone is caring for a person living with diabetes and cannot wake them up or they seem unresponsive, they need to contact 911 immediately.
Nocturnal hypoglycemia is a potential complication for people who use glucose-lowering medications to manage diabetes. Nocturnal hypoglycemia occurs when blood sugar levels drop below suitable ranges during sleep.
With proper awareness and management strategies, a person can minimize the potential effects of nocturnal hypoglycemia. By ensuring glucose levels are above a suitable range before bed, using continuous glucose monitors, and working with doctors, individuals can significantly reduce the risk of experiencing nocturnal hypoglycemia.