Diabetes does not usually cause headaches. But, while headaches are not dangerous, they may be an indication of poor blood sugar control in a person with diabetes.
Over time, periods of continuous high or low blood sugar can lead to serious and even life-threatening health complications, such as heart disease and kidney failure.
This article looks at the connection between diabetes and headaches and suggests ways to relieve diabetes-induced headaches.
Diabetes and headache: What is the link?
A person who manages their diabetes effectively may be less likely to experience headaches than someone who does not.
Not everyone with diabetes will experience headaches. People newly diagnosed with diabetes may be more likely to experience headaches because they are still working to manage their blood sugar levels.
Headaches associated with diabetes typically occur because of changes in blood sugar levels.
A headache can indicate that blood sugar levels are too high, which is referred to as hyperglycemia, or too low, which is called hypoglycemia.
The more that blood glucose levels fluctuate, the more likely it is that someone with diabetes will experience headaches. Headaches linked to these fluctuations are thought to result from changing levels of hormones, such as epinephrine and norepinephrine, which may constrict the blood vessels in the brain. This constriction is called vasoconstriction.
Hypoglycemia and headaches
Hypoglycemia is usually characterized by blood sugar levels of less than 70 milligrams per deciliter (mg/dL). Hypoglycemia is a serious condition, as glucose is the primary source of fuel for the brain.
Symptoms of hypoglycemia usually appear suddenly and can be much more obvious than the symptoms of hyperglycemia.
In addition to headaches, some of the symptoms of hypoglycemia include:
- blurred vision
- racing heart
Hypoglycemia can occur in people with diabetes if they take too much insulin or if they do not eat enough carbohydrates. It is important to manage diabetes carefully and treat symptoms of hypoglycemia quickly to avoid diabetes headaches and more serious compilations.
Hyperglycemia and headaches
Hyperglycemia results from too much glucose circulating in the blood. In type 1 diabetes, it is caused by a lack of insulin production. In type 2 diabetes, it is caused by the body's inability to use insulin correctly. Additional risk factors include:
- eating too much
- not exercising enough
- being stressed
Symptoms of hyperglycemia are often slow to appear. However, a headache is considered an early symptom of hyperglycemia. Other symptoms include:
- blurred vision
- excessive thirst
- increased urination
- slow-healing wounds
Hyperglycemia is a serious condition that should be treated quickly, as high levels of glucose can damage the blood vessels and nerves. If left untreated, it can lead to a buildup of ketones, a type of acid in the blood. A buildup of ketones can lead to coma and even death.
A person can manage hyperglycemia with dietary changes and medications. Keeping blood sugar levels under control will reduce the risk of headaches caused by diabetes.
Although over-the-counter painkillers may provide immediate relief in the short-term, they should not be relied upon in the long-term.
Over-the-counter painkillers, including acetaminophen and ibuprofen, may help with short-term symptom relief.
A person should speak to a doctor first to see if their diabetes has affected their kidneys, as people with kidney damage should avoid taking certain painkillers, including ibuprofen.
However, to completely relieve or stop headaches caused by diabetes, it is important to get blood glucose levels under control and practice good diabetes management. This can involve making lifestyle changes and taking or adjusting medication dosages.
A person should always consult a doctor before making changes to their diet, physical activity levels, or medication.
Treating headaches from hypoglycemia
The first step in treating a hypoglycemia-induced headache is to confirm that the pain has been caused by low blood glucose. This can be done by taking a blood glucose test.
Taking a blood glucose test is especially important for people who wake up with a headache, as it can be a sign of nocturnal hypoglycemia.
The American Diabetes Association recommend that people with low blood sugar consume 15 to 20 grams of simple carbohydrates or glucose before re-checking levels after 15 minutes. Once the blood sugar is back in the desired range, the headache pain should reduce.
Treating headaches from hyperglycemia
High blood glucose levels may be brought down with exercise.
If a person with type 1 diabetes is concerned about their ketone level, it is important to check their urine for ketones first, especially if blood sugar levels are above 240 mg/dL.
People with ketones in their urine should not exercise and should contact their doctor immediately, as exercise could increase their blood sugar levels further.
A person can also help prevent headaches by maintaining a healthy weight, eating nutritious food, and taking the correct medications.
When to see a doctor
Headaches can signal periods of either high or low blood glucose, which, if left untreated, can lead to life-threatening complications. Therefore, people with diabetes who are experiencing frequent headaches should consult their doctor.
It is important to contact a doctor immediately if:
- a headache is severe and impacts daily life
- blood sugar levels cannot be returned to a desired range
- other severe or persistent symptoms are present
Not everyone with diabetes will experience headaches, and diabetes is not the only cause of headaches.
People with diabetes who practice good diabetes management and keep their blood sugar levels under control are less likely to experience headaches. Avoiding hypoglycemia and hyperglycemia is the best way to reduce headaches and other diabetes symptoms, as well as more serious complications.
If headaches are severe or persist despite keeping blood sugar levels controlled, a person should seek further advice from their doctor.
Types of headache
Secondary headaches are caused by existing or underlying conditions, such as diabetes.
According to the International Classification of Headache Disorders, published by the International Headache Society, there are over 150 types of headaches.
Broadly speaking, headaches can be classified as either primary or secondary:
Primary headaches are ones that are not linked to another medical condition. Examples of primary headaches include migraines and tension headaches.
Secondary headaches are caused by underlying medical conditions or health issues and include the type of headache often experienced by people with diabetes.
Other causes of secondary headaches include:
- high blood pressure (hypertension)
- hormone fluctuations
- nerve disorders
- overuse of medication
The pain associated with either primary or secondary headaches can vary in severity and duration. Some people may not experience headaches often, while others can get a headache several days each week.
Depending on the type of headache, other symptoms may be present. For example, migraines can be linked with nausea and increased sensitivity to sound or light.
Diabetes headaches tend to occur frequently and cause moderate to severe levels of pain. A severe headache is considered one that significantly affects someone's ability to function as normal.