Nearly everyone has experienced a headache at some point in their lives. For some, a headache is a common occurrence, and a simple nap, some pain relievers, or a cup of coffee may relieve symptoms. However, sometimes a headache is so intense that it feels like something more serious is causing it. 

This guide from HealthTap breaks down the different types of headaches, the common causes of headaches, and which of the worst headache symptoms warrant a visit to the doctor. 

What is a headache?

A headache describes head pain felt around the whole head, side of the head, temples, sinuses, or behind the eyes. They can be either primary or secondary — headaches resulting from another condition are secondary headaches, while those without underlying causes are primary headaches. 

The most common primary headaches are migraine headaches, thunderclap headaches, tension headaches, and cluster headaches. Primary headaches can either happen once in a while or turn into persistent headaches, occurring several times per day for weeks or even months.

It’s hard to diagnose primary headaches because a brain scan can’t even really show that someone is experiencing a headache. This is because the brains of those with primary headaches don’t look very different from people without headaches. 

To diagnose a primary headache disorder and decide on the proper headache treatment, a doctor will check the patient’s history and perform a neurological exam. A doctor may also look at other factors in the patient’s medical history like high blood pressure, pain medication interactions, and hormonal changes. 

Sometimes, people use pain relievers like aspirin or ibuprofen too frequently to try and stop the throbbing pain of their headache, which can result in medication overuse headaches. This type of headache often occurs until the person lessens their usage of over-the-counter or  prescription pain medication (under the guidance of a doctor).

Secondary headaches, on the other hand, do result from an underlying health condition, such as encephalitis (brain inflammation), a sinus infection resulting in a sinus headache, or a blood clot.

It is important to diagnose such headaches, not only because treating the condition can get rid of the headache, but also because the underlying cause may be life-threatening. 

What causes headaches?

What causes a headache depends on what kind of headache it is. Primary headaches have causes that are very different from secondary headaches. 

For instance, migraines are often a result of changes in the brain’s electrical activity. These changes stimulate blood vessels in the back of the head, which connect to small nerves in the back of the neck. These nerves, in turn, stimulate a large nerve (the trigeminal nerve), which  passes pain signals to the brain. This final step is responsible for the pain felt during migraine attacks.

Migraines are also usually set off by triggers such as stress, lack of sleep, and alcohol. 

Unlike primary headaches, secondary headaches usually have an underlying cause. There are various causes of secondary headaches, some of which are generally nothing to worry about. 

For instance, hangovers lead to increased alcohol in the bloodstream, which can reach the brain. This widens blood vessels and puts pressure on the surrounding nerves, causing pain. 

While a hangover is usually nothing to worry about, other causes of secondary headaches can result in severe pain and warrant a doctor’s visit. The next section breaks down these potential causes. 

What are potential causes of serious headaches?

Many secondary headaches are due to factors like muscle tension, caffeine withdrawal, or dehydration. These should produce mild or moderate side effects that go away pretty quickly on their own. 

However, other secondary headaches are more serious and require at least a visit to the doctor — if not the emergency room. The following are potential causes of serious headaches to watch out for.

• Tooth infection
  An infected tooth can spread to the face or body (and even lead to death). This makes it important to address as soon as possible. While an infected tooth likely won’t cause pain in the brain’s nerves, it can cause pain in the face that is so intense that it radiates to the head.

• Heatstroke
  Heatstroke happens when the body overheats to 104°F or more. A throbbing headache is a common symptom of this condition.

• Head injury
  A head injury (with or without a concussion) can lead to a headache in the days or weeks following the event. 

• Severe dehydration
  Without enough water and electrolytes, the brain can actually shrink. This makes it pull away from the skull, putting pressure on surrounding nerves and leading to headache pain. 

• Stroke
  A stroke-related headache is a severe type of headache that comes on within seconds or minutes of the event. It affects more than half of people who experience a stroke. 

• Traumatic brain injury (TBI)
  Any physical trauma to the head that makes the brain move around in the skull is considered a TBI. Concussions are the most common TBI and need immediate treatment to prevent complications. Not taking time to rest can make the headache worse and may result in permanent concussion symptoms. 

• Meningococcal disease
  This refers to a bacterial infection that spreads to the meninges, which are the tissues covering the brain and spinal cord. The infection could cause severe inflammation, which could lead to pain. 

• Brain tumor
  If a tumor is large enough, it can press on the surrounding nerves, which can lead to headache-type pain. 

There are many other potentially serious causes of secondary headaches. However, just because a critical health condition isn’t causing the headache does not mean that a doctor’s visit is not necessary. 

What are some headache symptoms to worry about? 

Sometimes, serious health conditions do not present obvious symptoms. However, in most cases, it will be clear when someone is experiencing a medical emergency. 

If someone is experiencing a severe headache in addition to the following warning signs, it may be necessary to seek emergency care. 

• Unbearable, severe headache pain, especially for the first time.

• Pain that begins immediately after sneezing or coughing.

• Consistent pain in the same area of the head. 

• Sore, stiff neck.

• High fever (over 102℉).

• Bleeding from the nose or ears.

• Nausea and vomiting.

• Extreme dizziness.

• Problems walking or maintaining balance.

• Blurry vision.

• Weakness on one side of the face and body.

• Mental confusion.

• Slurred speech.

• Injury to the head.

• Animal or insect bite.

The American Headache Society even has a mnemonic device to help people recognize when a visit to the doctor is necessary — “SNOOP.” It stands for the following groups of symptoms: 

• Systemic signs and symptoms
  This refers to any symptoms that affect the entire body. It includes muscle pain and weakness, chills, shaking, fever, and weight loss. It also includes underlying health conditions, such as cardiovascular disease, which increase the risk of serious complications. 

• Neurological signs and symptoms
  This refers to any changes in cognitive functioning, such as extreme mental confusion, loss of memory, and personality changes. These symptoms could indicate a condition that affects the brain, such as stroke. 

• Onset
  How quickly a headache sets in could signify that something is wrong. If someone gets a severe headache seemingly out of nowhere, it could be a sign of a stroke or aneurysm. 

• Older age of onset
  In general, headache disorders start in younger people. If someone over 50 years of age gets a new type of headache, it could be a sign of a more serious problem. 

• Prior headache history
  If a headache is part of a pattern, it might not be something to worry about. However, if there’s an extreme change in intensity and frequency, it could be a potential sign that something is wrong.

Anyone can use the above to help identify a potentially serious cause of a headache and seek immediate treatment. A doctor will be able to diagnose a potential health condition depending  on the patient’s symptoms, medical history, and comprehensive medical tests, and then provide treatment options to fit the case. 

Getting virtual urgent care with HealthTap 

If, in addition to a headache, you experience symptoms like fever, mental confusion, and loss of balance, it’s important to seek emergency care right away. 

If you don’t have any serious symptoms but still have a throbbing headache, seeing a doctor can still help rule out potentially serious medical conditions.  

HealthTap can connect you with a low-cost healthcare professional so you can discuss your symptoms, get a diagnosis, and receive treatment — all through our virtual platform.

Schedule your appointment today to get headache relief.