Headaches are one of the most common health complaints I hear from my patients. Most headaches, while uncomfortable, are generally not a cause for concern, and can be treated with simple pain management strategies and over-the-counter (OTC) medication.
In this article, I’ll describe the differences between primary and secondary headaches and provide examples of the most common ones from each category. I’ll review both common and rare symptoms, and explain how these symptoms are categorized and diagnosed by doctors. This way, you’ll be able to make a more informed decision about whether your next headache should be treated with a glass of water, resting in a dark room, over-the-counter (OTC) medication, or medical attention.
The Two Main Categories of Headaches
Doctors think about headaches in two categories: primary and secondary. They may be equally painful, but the difference between these groups is in the cause.
- Primary headache: This is a condition in and of itself, and is not caused by another underlying condition. Over 90% of headaches are primary headaches. There are various types of primary headaches, and they can begin in the head’s blood vessels and nerves, or in the neck and face muscles. Triggers can include stress, diet, alcohol, changes in sleep habits, etc.
- Secondary headache: Secondary headaches are a result of another process or underlying condition in the body. In other words, a secondary headache is a symptom of something else going on that may merit medical attention. Causes can range from medication overuse, or caffeine withdrawal to something more serious, like an infection, blood clot, or brain tumor.
Types of Primary Headaches
Primary headaches happen in isolation, meaning the headache is the main issue and it’s not connected to another underlying health condition. They can be one-time occurrences or chronic, meaning they happen often over a long period of time.
Here are the most common types:
A migraine is the second most prevalent type of primary headache and is a common complaint in any primary care physician’s office. In fact, 30% of K Health users who chatted about a headache had symptoms that point to a migraine.
Cluster headaches are rarer and more painful than tension headaches or migraines. In fact, only one in 1,000 U.S. adults has experienced cluster headaches. These are relatively short-lived (minutes to hours) but the sufferer can have multiple episodes in one day. These cluster periods can last from weeks to months and are typically followed by intervals of full remission, with no headaches for months or even years.
Most attacks occur at the same time of day, especially at night a couple hours after you fall asleep, and cluster periods can occur around the same time of year.
Exertional or exercise headaches
As its name suggests, an exertional headache occurs with physical exertion and is often caused by activities that increase pressure in your chest or tense your abdominal muscles. This can be from heavy exertion, like running, or from something as innocuous as coughing.
A hypnic headache is a super rare, sleep-related primary headache that occurs in people over age 50. It is also called an “alarm clock headache” because it only occurs during sleep and can wake you up. Fewer than 200 cases have been reported as of 2010.
Symptoms of Primary Headaches
The primary symptom of a headache is pain in any part of the head. Headaches may come in the form of a sharp pain, a constant throbbing feeling, a tight or squeezing feeling, or a dull ache. You can differentiate between types by the following symptoms:
- Tension headaches: A constant pressure or pain, felt on both sides of your head.
- Migraines: A pulsating or throbbing pain felt on one side of your head, which can last anywhere from several hours to days. The severity of the pain can inhibit daily activities. Nausea, vomiting, and extreme sensitivity to light or sound are also common.
- Cluster headaches: These are painful enough to wake you from sleep. The pain is intense and occurs on one side of the head, often behind or around one eye. Typically, you may experience excessive tearing or redness of the eye or drooping of the eyelid on the same side as the pain. You may also experience nasal congestion or post-nasal drip in one nostril on the affected side.
- Exertional or exercise headaches: Exertional headaches come on quickly and usually begin shortly after the activity starts, although they can start after the exertion. They usually last a few seconds to several minutes. However, with repeated exertion, the intensity may build and last longer. Also, if the headache comes on more gradually and happens long after exertion, it may actually be a tension headache, triggered by muscle tension or dehydration.
- Hypnic headaches: Hypnic headaches occur at a consistent time each night, usually between 1-3 AM. In rare instances, they can occur during a daytime nap. The throbbing pain starts abruptly and can last from minutes to a few hours. The pain is usually in the front of the head, but you may also feel it on the side, or throughout the entire head.
Causes of Primary Headaches
There are many processes in the body that contribute to tension headaches, but at the most basic level they are related to increased sensitivity to pain.
They can be triggered by:
- Poor posture
- Eye strain
- Lack of sleep or poor sleep, which may be caused by sleep apnea, teeth grinding, or snoring
- Changes in diet
- Depression or anxiety
While the exact cause of migraines is not known, we know that changes in the brain and chemical imbalance in the brain likely contribute. Common triggers include significant stress, lack of sleep, menstruation, and dehydration, but migraine causes vary from person to person. Most migraine sufferers learn to recognize their symptoms and triggers, as well as what brings migraine relief.
The exact cause is unknown, but cluster headache patterns suggest that abnormalities in the body’s biological clock contribute to their onset. Unlike migraines and tension headaches, cluster headaches aren’t generally associated with triggers like hormonal changes, stress, or diet. However, once a cluster period starts, drinking alcohol can trigger more intense pain.
Exertional or exercise headaches
Exertional headaches can be caused by straining while making a bowel movement, coughing, running, heavy lifting, sneezing, or even sexual intercourse. The cause is unknown, but it may be related to increased pressure in the brain.
The exact cause of hypnic headache is unknown, but contributing factors may include sleep apnea, nighttime hypertension, poor breathing during sleep, or increased pressure in the brain when lying down.
Primary Headache Treatments
OTC medications can often provide significant headache relief. Drinking liquids can also be helpful, particularly if dehydration is the cause. Sleep, balanced nutrition, massages, or anything else that reduces stress can also relieve tension headaches.
There are many medications specifically designed to treat migraines. Some are available over the counter and others need to be prescribed by a doctor.
Migraine medications can be divided into two broad categories: migraine pain relievers and preventive medication, designed to reduce the number of migraines that occur. Pain relievers, whether OTC or prescription, are often taken during migraine attacks and aim to stop the symptoms. Preventive medication is usually prescribed when the frequency of migraines is high, and can be taken daily to help reduce the frequency and severity of migraine attacks.
While there is no cure for cluster headaches, some medications and treatments have been known to be effective to stop and prevent these episodes. If you are having these severe and debilitating headaches, you should definitely speak with your doctor to discuss a treatment plan.
Exertional or exercise headaches
Exertional headaches can typically be prevented by having a short warm-up period before exertion or by avoiding the specific exercises which trigger the pain. Most respond to OTC or prescription anti-inflammatory medications.
While disruptive and painful, hypnic headaches are benign. Lithium carbonate can be used to treat hypnic headaches though this medication has many side effects. Other treatments include bedtime doses of caffeine and indomethacin. Talk to a doctor to find the best medicine for you.
Types of Secondary Headaches
The following are the most common types of secondary headaches.
Post-traumatic headaches are those that begin within seven days of a head injury. If the pain is severe, if the trauma was serious, or if you lose consciousness from the trauma, you should seek immediate medical attention. Even if the symptoms are mild, you should still have your doctor evaluate you. With this type, the accompanying symptoms can last for a few months.
Headaches from pain medication overuse
Chronic headaches can develop as a result of overusing certain pain medications, particularly if you take them more than 2-3 days per week.
The pain of a sinus headache is associated with pressure or congestion in your sinus cavities. Sinus headaches are common, but if they endure for more than a week it may indicate that you have a bacterial sinus infection, or sinusitis.
How to differentiate a sinus headache from a migraine
Sinus headache symptoms, including facial pain, pressure, and congestion, can appear with migraines or cluster headaches. In fact, many people confuse sinus headaches with migraines. If your sinus pain gets worse when you lean forward, or if you have bad breath or a runny nose, it’s more likely that your pain is caused by your sinus cavities.
Symptoms of Secondary Headaches
Symptoms that may be associated with post-traumatic headaches are:
- A dull ache that gets worse from time to time
- Trouble concentrating
- Tiring quickly
- Memory problems
Headaches from pain medication overuse
The following symptoms may indicate overuse of pain medication:
- Daily, chronic headaches, usually felt upon waking
- Improvement with pain relief medication, but pain returns when medicine wears off
- Symptoms vary, but can include nausea, irritability, anxiety, restlessness, difficulty concentrating, memory loss, and depression
The pain from a sinus headache is felt in your cheeks and forehead. The congestion in your sinuses may also cause a stuffy or runny nose.
Causes of Secondary Headaches
Unlike primary headaches, which occur in isolation, secondary headaches are signs of an underlying problem, condition, or disease.
There are numerous conditions that may cause your pain, including the following, which vary in severity:
- Sinus infection
- Caffeine withdrawal
- Medication overuse
- Another existing, known medical condition such as high blood pressure
- Head injury, such as a concussion
- Bleeding in your brain
- Brain tumor
More specifically, if you have these types of secondary headaches it could be caused by the following:
- Post-traumatic headache: As mentioned, post-traumatic headaches happen after a traumatic head or brain injury. While not known for certain, studies suggest that these headaches are caused by the release of certain chemicals, the swelling of brain structures, or even the shrinking of the brain as a result of the accident.
- Sinus headaches: Sinus headaches are caused by pressure built up in your sinus cavities due to congestion.
Secondary Headache Treatment
Short-term treatment may include anti-inflammatory medication or pain relievers. If they persist, your doctor might prescribe preventive medicines such as blood pressure pills, antidepressants, or anti-seizure medicine. For longterm sufferers, non-drug treatments can also provide pain relief, including biofeedback, physical therapy, nerve stimulators, relaxation therapy, or cognitive behavioral therapy.
Headaches from pain medication overuse
One of the most important parts of treating medication overuse headaches is to stop taking the medication you’ve been overusing. Just after you stop your medication, you may have a period of worsened headaches, so I recommend doing this under the care of your doctor. Hydration, rest, and talking with your doctor about gradually reducing your dose(s) of medicine may shorten this period of worsened pain. Alternatives to pain medication include talk therapy, biofeedback, and targeted physical therapy.
If you’ve had your sinus headache for less than a week, OTC medicine and generous hydration should relieve the pain. However, it has lasted a week or longer, you may have developed a bacterial sinus infection. In that case, talk to a doctor for antibiotics.
Differentiating Between Primary and Secondary Headaches
When my patients come to me complaining of a headache, I usually do a quick triage to rule out more serious neurological symptoms such as weakness, numbness, tingling on one side of the body, or vision issues just to name a few. With those out of the way, I’ll then ask about past and current symptoms, triggers, where the pain is located, what are the other characteristics of the pain, and if they have any high-risk medical conditions. These answers provide a more complete picture of whether additional medical tests need to be done. If necessary, I’ll perform additional medical examinations to see if I can discover any underlying conditions that may be causing a secondary headache. The more information I have, the more successful I can be at narrowing down possible scenarios to rule out the more serious health cases and focus on the right course of treatment.
In most cases where patients complain of a severe or new type of headache, a doctor will want to perform additional testing to determine the cause of it. These tests might include a physical and neurological exam, blood work, and imaging, including x-rays, MRIs, and/or CT scans.
When to See a Doctor for Your Headache Pain
For any of the primary headaches discussed above, drinking fluids, resting, or taking OTC medications like acetaminophen (Tylenol) or ibuprofen (Advil) should help to relieve pain. If these treatments don’t work, if you suffer from headaches more than once a week, or if your pain interferes with your normal functioning, I recommend speaking with a doctor. If it’s your very first headache (especially in children under five or adults over 50) or if you notice changes in the pattern of your chronic headaches, it’s also a good idea to talk to a doctor.
Consider going to the ER or seek immediate medical attention if:
- It’s the worst headache you’ve ever had
- Pain is sudden and reaches maximum intensity quickly, or feels like a “thunderclap” sensation
- You faint or experience seizures
You should also see a doctor right away if you are feeling confused or have neurological symptoms such as:
- Weakness, numbness, or tingling on one side of your body
- Difficulty speaking or walking
- Change in vision (blurred or double vision)
- Loss of motor skills
- Loss of balance
- Sudden eye pain, eye swelling, or drooping in your eyes
While headaches are common, it is important to identify high-risk symptoms, and then determine whether they are caused by a primary or secondary headache. Learning to identify the symptoms that accompany your headache will help you define whether it is a common, benign headache, or something more serious that needs urgent medical attention.
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