Headache Review
As many as half of the world's adults have had a headache at some point last year. Some have them nearly every day. They can be very painful and debilitating, and a lot of research is being done on them.
There are many different types of headaches, it turns out. And not only do they affect different areas of your head — they have different causes and are triggered by different factors too. A quick survey at home revealed one of us gets headaches mostly when we’re hungry. Another, after being in the sun for too long. Me, when I’m stressed.
This month we asked scientists and clinicians to share the facts on all things Headaches. Are they in our minds, or is it all about brain chemistry? Can fatigue or poor sleep cause headaches? Can we prevent them? And how can we treat them? This science-backed guide will help you understand headaches without giving you one. Here's what we found...
NUMBERS
Meta-Index
50%: adults who had headaches last year.
1/20: people who have headaches nearly every day.
1/5: people who suffer from migraines.
25 million: workdays that are lost to migraine every year in the UK.
10%: people with migraine who have aura.
2x: more risk of migraines in women than in men.
1897: year when aspirin was invented.
61: painkillers taken per year by an average American.
ORIGIN STORY
From Willowbark to Aspirin
Willow bark was used as an analgesic going back 3500 years. The ancient Egyptians used it as a remedy for aches and pains of all sorts, including headaches. Hippocrates, the Greek physician, said that willow leaves could be used for pain relief. But it took a bit longer to work out why. It was not until the 19th century, however, that the active ingredient in willow bark and leaves was discovered. Chemists first isolated some crystals from their leaves (which they called salicin) and then a stronger powder (salicylic acid). This compound was an irritant, though, so scientists tried to change its structure to avoid this.
In 1852, French chemist Charles Gerhardt achieved it, but the compound he made was not stable enough and he gave up. Over in Germany, chemists at Bayer did not. In 1897, by heating salicylic acid with acetic anhydride, they made acetylsalicylic acid, which would soon be known as aspirin. Yet, little was known about how aspirin worked. In fact, British pharmacologist John Vane won the Nobel Prize for Physiology or Medicine in 1982 for figuring out. He demonstrated that aspirin was blocking the mechanisms leading to inflammation.
As the benefits of aspirin became clear, so did its side effects. Luckily, other compounds started to be developed and added to our arsenal of over-the-counter painkillers. Paracetamol was discovered in 1956. Ibuprofen was first made in 1962. Drugs like these are extremely helpful for mild headaches but do not work so well with others. One example is migraine, for which specific drugs have been developed (of which sumatriptan is perhaps the most widely used). Migraine is not just a bad headache, however: it usually triggers recurring pain attacks on one side of the head, which are extremely disabling and can last hours.
As you can see, there is no sign that headaches will be going away anytime soon. Even cyborgs have them — sort of. Neil Harbisson, the world’s first legally recognized cyborg, has an antenna wired to his brain which, he jokes, gives him some sort of ‘antenna-ache’. Luckily, painkillers still do the trick.
CONSENSUS
Can you prevent headaches?
Before we start, we should stress that “headache” is just an umbrella term for “head pain”. There are, in fact, hundreds of types of headaches. Among primary headaches, there are three important types: migraine, tension-type headache and cluster headache. Primary headaches are not dangerous as such, but may cause significant pain and disability. In fact, migraine is the single most disabling condition among people under 50 according to a 2017 study.
There are also secondary headaches. These are caused by a different condition that just happens to trigger pain-sensitive areas in the neck or head, and so the headache is really a warning sign of an underlying condition such as brain bleed or tumors, infection or head injury. “Secondary headaches are treated when the underlying disease is treated (operation of the brain tumor). Primary headaches can be treated in 2 ways: acute treatment and preventive treatment” writes Prof Arne May from the University of Hamburg. “The preventive treatment is based on medications and non-medical treatment”, he says, adding that “around 70% of all patients have a benefit from a preventative treatment.”
“There are a number of drugs that are able to reduce the number of headache days through different mechanisms” writes Prof Tony Dickenson from University College London. This includes drugs used for other conditions such as depression (triptans that modulate serotonin activity like amitriptyline) or high blood pressure (beta-blockers like propranolol). There are also other, more long-term treatments he says, like botulinum toxin injections (yes, that’s Botox — which blocks neuron-muscle connections) and antibodies against CGRP (to block these receptors that contribute to the transmission of pain).
There are three types of prevention strategies depending on what triggers your headaches (worry not, we’ll talk all about triggers in the next section). According to Prof Antonio Russo from the University of Campania, “pre-emptive treatments are used when well-identified triggers exist, and patients should be instructed to intake the drug before the trigger exposure (for example to prevent migraine attacks induced by physical exercises).” Then there’s short-term treatments, which “are used when patients are undergoing a time-limited exposure to a trigger factor, such as migraine attacks related to menstruation,” he says. Finally, “maintenance prevention is used when patients, due to the migraine attacks experienced in the course of the entire month, need ongoing treatment.”
CONSENSUS
Is fatigue linked to headaches?
Headaches are rarely caused by a single trigger and so their prevention can get complicated in real life. Different things can push the balance of chemicals in our brain away from its healthy basal condition. This is what we call triggers, because they will affect how brain networks function. “Any deviation from a person’s regular daily program e.g. missed meals, lack of sleep, may trigger an attack,” explains Dr Anna Andreou from King’s College London. “With the term ‘trigger’ we indicate a series of stimuli that may have an effect on a susceptible brain (i.e. the migrainous brain) and lead to a cascade of cellular and molecular brain changes resulting in an acute migraine attack,” writes Prof Antonio Russo, headache expert from Italy.
Because headaches are usually produced by a combination of factors, “the only way you could prevent having a headache or migraine is to increase the body threshold of having a headache”, according to Prof Fayyaz Ahmed from Hull York Medical School. This can be achieved by a healthy lifestyle, he explains: “good balanced food, good night sleep, regular exercise, hydration, etc.”
When you have a busy period at work and are a little stressed by an ever-growing to-do list, chances are your head will start to hurt. Indeed, fatigue is one of the most common triggers of headaches. “Fatigue from stress or actual physical fatigue is one of the triggers for migraine and tension-type headache,” writes Dr Chanawee Hirunpattarasilp from HRH Princess Chulabhorn College of Medical Science. Most patients with migraines report fatigue symptoms every day, and fatigue can precede or follow pain attacks according to Dr Andreou. “Fatigue can also be a symptom of a migraine attack before the actual headache begins and/or after the headache phase”. Almost all patients with cluster headache report fatigue as well, she says. “Headache can lead to fatigue and fatigue could lead to headache,” explains Prof Ahmed, who says both can co-exist.
Fatigue is definitely not the only factor that can cause headaches, however. “Others include hunger through skipping meals and bright light,” writes Prof Dickenson. Lack of sleep (or too much of it) is also an important trigger for migraine, although no link has been shown as yet for other headaches. “Hence when we advise people for a healthy lifestyle, we tell them to sleep on time and have at least 6-8 hours of good night sleep,” says Prof Ahmed.
CONSENSUS
Does acupuncture work for headaches?
Acupuncture is a form of treatment that consists of having tiny needles inserted in specific areas of your body - and it seems to be getting quite a bit of attention lately. After thousands of trials and decades of research, however, it has consistently failed to prove its efficacy for therapy. Some of these studies have suggested that some effects may exist, but these are often small so it’s about whether they would make any difference anyway.
Having said that, some evidence does suggest that it may work for chronic headaches or migraines specifically. “If you are the sort of person who gets bad headaches and you go for a course of acupuncture treatments, say, once a week for 8 to 12 weeks, then after the course of treatment, your headaches will become less frequent or less severe,” says Prof Andrew Vickers from the Memorial Sloan Kettering Cancer Center.
Yet, Prof Ahmed warns that other studies on acupuncture have not achieved any benefits, which suggests that any effects are indeed probably mild. It is not really clear how it should work either. “It doesn't matter so much where exactly the needles are inserted, but that some needles are inserted and that the patient experiences the general experience of having a course of acupuncture,” writes Prof Vickers. In fact, a 2005 study found that acupuncture was just as effective as sham acupuncture (placebo) in reducing migraines, although both helped more than doing nothing.
“It is certain that it does not harm you so, if it is available, go for it unless it is too expensive as the evidence of its efficacy is very low” advises Prof Ahmed. Perhaps unsurprisingly, compliance was high and adverse effects were rare in migraine patients treated with acupuncture, a trial published this year has found.
CONSENSUS
Is there a psychological component to headaches?
100% Affirmative via 8 experts
Remember what we just told you? Placebo has some effect on headaches. That brings us to our last question — surely there must be a psychological component to headaches, then?
Let’s go back to migraine again as it is one of the best-known types of headache. “A headache with a clear biological and genetic background such as migraine is modulated by psychological factors such as stress,” says Prof May. “Behavioral therapy is certainly helpful in targeting and treating migraine,” he adds. “Psychological factors such as depression and anxiety, as well as catastrophizing or rumination of pain experience [constantly thinking about it] are common in migraine patients and they significantly contribute to its worsening,” writes Prof Russo. He adds that “migraine is not just a physical painful experience but also an emotional burden” as it can have knock-on effects on your school or work productivity, your life goals, your feelings and your relationships.
You may get a headache when you worry about something. However, “primary headaches do not have a psychological cause”, explains Dr Andreou. In other words, being worried won’t give you a headache by itself. Yet “certain psychological conditions, such as depression, are common comorbidities in headache sufferers, especially in chronic patients,” she says. According to Dr Hirunpattarasilp, “antidepressant medications are effective in preventing attacks of certain types of headache. Hence, the patient's psychological status should be assessed in patients with headaches.”
Quick Answers
What headache medication is best? It really depends on our type of headache and on how frequent, severe, and long the pain is. Don’t panic, your doctor will know what’s best for you.
Can painkillers cause headaches? Yes. There’s something called ‘medication overuse headache’, where painkillers stop helping and actually start causing headaches. Stick to the dose limits.
Do we outgrow migraines? Migraines are most common among people of ages 20 to 50. Some older people still have migraines, but they do become less common as we age (particularly among women).
Are they hereditary? In most cases, yes. Genetics is anything but straightforward, yet having a strong family history of migraines will increase your risk.
When do pain attacks kick? Mostly in the early morning or late at night, but there is huge variability across people.
Can animals have headaches too? The jury is still out on this. Some rare cases have been reported where animals behaved like we do when we have a headache, but we can’t know for sure.
Top Answer
Is there a psychological component to headaches?
Headache is one form of pain, and all pain can be influenced by psychological factors such as our mood, beliefs, and social relationships. Also, if we are tense or stressed, we might unconsciously show this with our bodies by tensing our shoulders or grinding our teeth - both of which can cause headaches. However, it is important to say that just because there can be a psychological component to headaches, doesn’t mean that the pain is any less real, or that it is ‘in our head’.
Janet Bultitude from University of Bath.
Takeaways
There are about 200 different types of headaches, but migraines are the best known.
You can treat headaches before and after they happen, both with drugs and with lifestyle changes.
Some drugs for headaches include repurposed compounds used for heart conditions or depression. Others are more recent, and new ones are coming up.
If you know some things that usually give you headaches are about to happen, taking preventive treatment will help.
Fatigue could lead to headaches... and vice versa. The same goes for stress or lack of sleep, it seems. Avoid them!
Acupuncture may work for about half the people but probably due to the placebo effect.