Why Do You Get a Headache at the Same Time Every Day?

Migraines and cluster headaches can occur at the same time each day, and circadian rhythms—or sleep-wake cycles—may explain why. The connection seems to be the hypothalamus, a part of the brain that plays a role in circadian rhythms and the two headache types.

Researchers found around half of people with migraines and cluster headaches had a consistent pattern of headaches at the same times daily based on sleep-wake cycles. Here's what else you need to know about recurring headaches every day and what to do if you have them.

What Causes Migraines and Cluster Headaches?

While scientists have suggested a genetic cause for migraines, they don't know what causes cluster headaches. Rashmi Halker Singh, MD, an associate professor of neurology at Mayo Clinic who sits on the Board of Directors of the American Headache Society, told Health that, specifically, genetic factors play a role in both cluster headaches and migraines.

"Migraine is much more common, people want to know why this happens to them," said Dr. Halker Singh. "This...study is really interesting in that it helps validate that—it helps identify that there are more genes involved in migraine, for instance, and also helps to point to additional brain areas that are important to [the presence of] migraine as well."

Mark Joseph Burish, MD, PhD, of the University of Texas Health Science Center at Houston and a member of the American Academy of Neurology, told Health that a family history of these kinds of headaches raises one's risk of experiencing them. Dr. Burish echoed Dr. Halker Singh's belief that this is due to genetic links.

"A family history of cluster headache also raises your risk of having cluster headache, though not nearly as strong as migraine. Actually, being a smoker, for reasons we do not understand, increases your risk of having cluster headaches," said Dr. Burish.

Migraines vs. Cluster Headache Symptoms

A cluster headache generally goes on for 30 to 90 minutes. A migraine can last a full day or even several days if it goes unattended. A person will usually experience one migraine at a time, while cluster headaches can clump together up to eight in one day.

In addition, you might experience a moment of reprieve between cluster headaches. That's not the case with migraines. The pain from migraine could fluctuate through the day but doesn't subside completely and lingers.

Cluster headaches involve just one side of the head—think around the eye or temple. Migraine headaches can be located all over the head.

The Timing of Headaches

Having headaches every day has a link to how the body goes through its sleep-wake cycle. One meta-analysis that Dr. Burish co-authored examined all available studies on migraine and cluster headaches that involved circadian systems.

The researchers paid close attention to the time of day and the time of year when these headaches occurred. Circadian rhythms are heavily associated with light and dark, making those data points highly relevant.

They also assessed studies on the presence of these headaches and hormones like melatonin and cortisol, which are both tied to one’s circadian system.

Dr. Burish said that cluster headaches are well known among specialists “to have a precise daily cycle,” which meant they weren’t surprised to see this connection with the circadian system. It was the migraine data that was more surprising.

“We were surprised to find that migraine has such strong circadian connections—50% of patients report headaches at the same time of day, there are lower melatonin levels in patients, and there are genetic connections to circadian genes or genes controlled by the biological clock,” explained Dr. Burish.

The Link Between Headaches and Circadian Rhythms

Dr. Burish and his team devised a hypothesis about the hypothalamus and headaches. The hypothalamus regulates many bodily functions, including sleep cycles, body temperature, and even hunger. This regulation is also seemingly connected to the timing of headaches every day.

“The hypothalamus is known to activate at the beginning of a migraine headache and at the beginning of a cluster headache. The hypothalamus also controls your circadian rhythms, so we think that the headaches are tapping into the circadian rhythm system,” said Dr. Burish.

Dr. Halker Singh explained it’s important to remember that migraines and cluster headaches are two very different medical conditions. The meta-analysis also reinforced how a circadian rhythm can regulate a phenomenon like a cluster headache, added Dr. Singh.

Next Steps in Headache Research

One limitation of the meta-analysis co-authored by Dr. Burish was a lack of information on the factors that could influence a person’s circadian cycles. When asked how having this information could further their understanding of these headaches and how they behave, Dr. Burish said there would be “more detail about the best way to help patients.”

One consideration would be headaches and night shift work. “For example, working the night shift changes your circadian rhythms because you are awake and active when your body naturally would be asleep,” explained Dr. Burish. “If we find that working the night shift changes your headaches in a certain way, we could try to design drugs that either mimic or counteract the effects that the night shift has on your circadian rhythms.”

Dr. Halker Singh added that this kind of research is incredibly validating for people who live with these headaches. It could offer an answer to those searching for why the headaches are happening.

“We don’t have a test at this time to give a diagnosis for migraine. The diagnosis comes by talking to my patients and helping them come to a diagnosis—it can be validating to have research that shows abnormalities that correlate to what’s going on with them,” explained Dr. Halker Singh.

Dr. Halker Singh added being hopeful about potential future research that could lead to new treatments. According to Dr. Burish, that’s part of the plan.

“We think that looking more into the effects of the circadian rhythms on the hypothalamus, headache genes, and current headache medications is the next step,” said Dr. Burish. “With that information, we hope we can identify specific triggers for the headaches that we can then target with medications.”

Preventive Measures for Cluster Headaches and Migraine

There are treatment options for these kinds of headaches. In terms of medications, the options fall into two major categories: acute medications and preventative medications.

Acute medications are things taken during the headache to break it. Preventative medications are things taken regularly to reduce the frequency and intensity of headaches every day.

“Some of the preventive treatments for cluster headache and migraine, like prednisone and melatonin, are known to alter the circadian clock. But there are not a lot of other current medications that alter the circadian clock,” explained Dr. Burish.

Dr. Burish also noted that a better understanding of the role of the circadian clock in headaches may lead to the development of new drugs. In other words, “to prevent the headaches when they are most likely to occur,” said Dr. Burish.

When Should I Worry About Daily Headaches?

Knowing when to be concerned about daily headaches can depend on your headache pattern. Some people can have a pattern of daily headaches, but one reason to see a healthcare provider is if that or any regular pattern of headaches changes.

It's also best to see a provider if you frequently have headaches—including headaches every day—and you don't know what's causing them. Medical attention is necessary for the following:

• First-time headaches, particularly if they happen after age 50
• A headache that occurs following strenuous activity
• Headaches that affect sleep by either waking you up or making it hard to sleep
• Headaches following head injuries
• Headache with a history of cancer or a weakened immune system
• Headache with other symptoms such as vision problems, slurred speech, fever, nausea, loss of balance, weight loss, or memory loss
• A lasting headache for a few days
• Severe headaches in one eye with redness
• Sudden, explosive, or violent headaches
• A worsening headache, especially in the morning
• A "worst-ever" headache
  

A Quick Review

For people with cluster headaches or migraines, having headaches every day—especially at the same time daily—may be normal. Research has suggested that this pattern may be due to hypothalamus activation in the brain, which affects headaches and circadian rhythms.

There are ways to help treat and prevent daily headaches, so see a healthcare provider for a treatment plan. You'll also want to see a provider for frequent headaches without knowing the cause, headaches accompanying worrisome symptoms, or changing headache patterns.