If a headache occurs with blurred vision or causes it, it may be due to an underlying condition such as migraine and low blood sugar. Rarely, it can be a sign of a medical emergency.
The various conditions causing both headache and blurred vision will usually have additional symptoms. Some of these conditions can have serious complications, so people should contact a doctor if they have severe symptoms.
This article will discuss five possible causes of a headache and blurred vision, treatment options, and when to contact a doctor.
Headaches are very common, and most people have experienced them before. While less prevalent, dozens of conditions may cause blurred vision.
However, doctors associate far fewer conditions with both blurred vision and headache, especially when they occur at the same time.
Some conditions that can cause simultaneous headaches and blurred vision include:
Migraine affects at least
Some of the other symptoms associated with migraine include:
- sensitivity to light and sound
- nausea and vomiting
- blind spots
- tunnel vision
- zigzag lines that move across the field of vision
- partial or complete temporary loss of vision
- objects seeming closer or further away than they are
- seeing an aura of light around objects
Most people experience visual problems before the pain sets in, but they can also occur during the headache itself.
Visual symptoms of migraine are short-lived and tend to last an hour or less. People can typically treat the symptoms of migraine with over-the-counter (OTC) pain relievers, such as ibuprofen and aspirin, or prescription medications, such as sumatriptan or ergotamine.
The sooner someone takes these medications in the course of the migraine, the more effective they usually are.
Low blood sugar
Blood sugar levels naturally rise and fall throughout the day and between meals.
However, if someone’s blood sugar levels get too low — less than 70 milligrams per deciliter (mg/dL) — they become hypoglycemic. Without treatment, hypoglycemia can be very dangerous.
The condition can cause headaches and blurred vision. Other signs and symptoms of low blood sugar levels include:
- feeling anxious or nervous
- sweating, clamminess, and chills
- feeling shaky
- fast heartbeat
- dizziness or lightheadedness
- irritation or impatience
- pale skin
- clumsiness or coordination problems
- lack of energy
- numbness or tingling in the tongue, lips, or cheeks
If a person thinks their blood sugar levels are too low, they may want to consume food with sugar or carbs, such as fruit juice. They can check their blood glucose levels if they have an underlying condition such as diabetes.
When blood glucose levels fall below 70 mg/dL, the American Diabetes Association suggests following the 15–15 rule. This means eating 15 grams (g) of carbs, waiting 15 minutes, then retesting glucose levels. If they are still low, a person should repeat the process.
People with conditions that can cause severe hypoglycemia, such as diabetes, may receive a glucagon kit to keep at home. Glucagon is a hormone that can help manage blood glucose levels. A healthcare professional will teach the person how and when to use the kit.
The conditions above are the most common causes of headaches and blurred vision. However, some less likely causes include more serious medical conditions that require immediate medical attention. These include:
A stroke can occur when a blood clot blocks a vessel carrying blood to the brain. Doctors call this an ischemic stroke. Less commonly, a stroke may happen when a blood vessel in the brain ruptures. Doctors call this a hemorrhagic stroke.
Strokes are responsible for
They can cause blurred vision in one or both eyes and a sudden, severe headache. Other symptoms include:
- numbness or weakness of the arm, face, or leg, especially on one side of the body
- difficulty speaking and understanding speech
- trouble walking, dizziness, and loss of coordination or balance
Without prompt treatment, strokes may cause life-threatening and permanently disabling complications. If a person thinks they or someone around them is having a stroke, they should call the emergency services immediately.
Traumatic brain injury
A traumatic brain injury (TBI) is an injury that interferes with normal brain functioning. They are the result of trauma: for example, a bump, hit, blow, or penetrating object. A concussion is one type of TBI that occurs as a result of a blow to the head.
The specific symptoms of a TBI depend on the part of the brain that the injury has affected and the extent of the damage. Although some signs of TBI can show up immediately, others can take days to weeks to appear.
People with mild TBI often experience a headache and blurred vision. Other common signs of mild TBI
- dizziness and lightheadedness
- ringing in the ears
- a bad taste in the mouth
- changes in mood or behavior
- sensitivity to light or sound
- loss of consciousness for a few seconds to minutes
- difficulty with attention, thinking, memory, or concentration
- a change in sleep habits
- nausea and vomiting
People with moderate to severe TBI often experience a headache that continues to worsen over time. Other signs of a moderate to severe TBI include:
- slurred speech
- convulsions or seizures
- inability to wake up
- loss of coordination
- loss of consciousness
- persistent vomiting and nausea
- numbness or tingling in the arms or legs
- increasing confusion, agitation, or restlessness
Severe TBI can be life threatening without treatment.
Mild TBIs, such as concussions, may only require monitoring and self-care. People with a mild TBI should temporarily limit doing certain activities that can stress the brain or increase the risk of re-injury, such as computer work or playing sports.
People with moderate to severe TBI need emergency care and should seek immediate medical attention.
Carbon monoxide poisoning
Carbon monoxide is an odorless, colorless, tasteless gas present in the fumes from burning fuel. It can be very dangerous, and more than
When people breathe in carbon monoxide, it binds to hemoglobin, which is the red protein in blood that carries oxygen around the body. When hemoglobin is bound to carbon monoxide, the blood cannot carry oxygen to organs and tissues.
Carbon monoxide poisoning causes a variety of symptoms as it deprives the body and brain of oxygen.
A headache and vision problems, such as blurred vision, are common signs of carbon monoxide poisoning. Additional symptoms include:
- upset stomach and vomiting
- chest pains
- flu-like symptoms
People with mild to moderate carbon monoxide poisoning should get away from the poisonous gas and seek immediate medical treatment. They should also call emergency services.
Individuals can prevent accidental carbon monoxide poisoning by installing carbon monoxide detectors in their homes.
Treatment for headaches and blurred vision varies greatly because they depend on the underlying cause of these symptoms. If a person has these symptoms, a doctor can diagnose their source and prescribe an appropriate course of treatment.
For example, if they result from migraine, a doctor can recommend medications and pain relievers that can reduce the severity of their symptoms. Conversely, if they result from a stroke, a doctor may administer a thrombolytic, which is a medication that can break up clots in the blood.
People who think they have had a migraine headache for the first time should contact a doctor. It is important to treat the condition as soon as possible, and a doctor can help a person learn the warning signs of migraine and know when to take medications.
If a person thinks their symptoms result from mild hypoglycemia, they can try eating a carbohydrate-rich snack. People experiencing signs of moderate or severely low blood sugar should contact a doctor.
Anyone experiencing signs or symptoms of a stroke, carbon monoxide poisoning, or TBI should also contact a doctor right away.
Some people have blurred vision and a headache for a relatively short time before making a full recovery. If a person has additional symptoms, they may require medical attention.
Common causes include migraine and low blood sugar. However, more severe conditions, such as stroke and traumatic brain injury, can also cause headaches and blurred vision. If a person has symptoms of these conditions, they should seek immediate medical attention.