Chronic Migraine

What chronic migraine is

Migraine is a neurological disease with attacks of moderate to severe throbbing headache, often one-sided, with nausea and sensitivity to light and sound, sometimes preceded by aura. Most people have episodic migraine, with fewer than 15 headache days a month.

Each year, about 3% of people with episodic migraine progress to chronic migraine. The brain's pain-processing pathways become sensitized, so the threshold for attacks falls. Headaches often become less distinct: many days have a background headache with superimposed full migraine attacks.

Symptoms

• headache on most days, often for weeks at a time
• migraine attacks: throbbing pain, nausea, vomiting, sensitivity to light, sound and smells
• milder "tension-like" headaches in between
• neck pain and stiffness
• fatigue, poor concentration ("brain fog")
• sleep problems
• dizziness or vertigo in some people
• low mood and anxiety

Causes and risk factors

Medication overuse headache

Using acute headache medicines too often can make headaches more frequent. Medication overuse headache is defined as using:

• simple pain relievers (acetaminophen, ibuprofen, aspirin) on 15 or more days a month, or
• triptans, combination pain relievers or opioids on 10 or more days a month

for more than 3 months. Opioids and butalbital-containing medicines carry the highest risk. Many people with chronic migraine have medication overuse, and reducing it often improves headaches.

Diagnosis

Chronic migraine is diagnosed clinically. A headache diary recording headache days, severity, medicines and triggers for at least a month is the key tool. Doctors ask about the headache pattern, acute medicine use, sleep, mood, caffeine and other conditions, and perform a neurological examination.

Brain imaging is not needed for typical chronic migraine with a normal examination. It is done for red flags: sudden onset, new headache after 50, neurological signs, or headaches worse on lying down (possible raised pressure, as in idiopathic intracranial hypertension).

Treatment

Preventive treatment

Prevention is the cornerstone. Options include:

• CGRP monoclonal antibodies (erenumab, fremanezumab, galcanezumab, eptinezumab): monthly or quarterly injections or infusions targeting a key migraine pain molecule. Well tolerated and effective.
• Gepants for prevention (atogepant, and rimegepant every other day): oral CGRP blockers.
• OnabotulinumtoxinA (Botox): injections at 31 or more sites around the head and neck every 12 weeks, FDA-approved specifically for chronic migraine.
• Topiramate: an oral medicine with evidence in chronic migraine; side effects include tingling and word-finding difficulty; avoided in pregnancy.
• Other oral preventives: beta-blockers (propranolol), amitriptyline, candesartan, and valproate (avoided in people who could become pregnant).

Preventives are usually tried for 2 to 3 months (6 months for Botox) before judging response. A 50% reduction in headache days is considered a good result.

Acute treatment

• triptans, NSAIDs, gepants (ubrogepant, rimegepant) or lasmiditan for attacks, while keeping within safe frequency limits
• anti-nausea medicines
• avoiding opioids and butalbital

Treating medication overuse

Reducing or stopping the overused medicine, ideally with a preventive started at the same time. Headaches may worsen for 1 to 2 weeks before improving.

Lifestyle and behavioral approaches

• regular sleep and wake times
• regular meals and hydration
• moderate, consistent caffeine intake or gradual reduction
• regular aerobic exercise
• weight management
• cognitive behavioral therapy, relaxation training and biofeedback
• treating depression, anxiety and sleep apnea

Devices

Neuromodulation devices (external trigeminal nerve stimulation, non-invasive vagus nerve stimulation, remote electrical neuromodulation) are options for some people.

Outlook

Chronic migraine is treatable. Many people return to episodic migraine with effective prevention and reduced medication overuse. Relapse can occur, so long-term management is common.

Frequently asked questions

What is chronic migraine?

Chronic migraine is headache on 15 or more days a month for more than 3 months, with migraine features on at least 8 of those days. It usually develops from episodic migraine and is one of the most disabling neurological conditions.

What causes migraines to become chronic?

Common factors include frequent use of pain relievers, high attack frequency, high caffeine intake, obesity, poor sleep, sleep apnea, depression, anxiety and stressful life events. Reducing medication overuse and treating these factors can help reverse the process.

Does Botox work for chronic migraine?

Yes. OnabotulinumtoxinA is FDA-approved for chronic migraine. Injections every 12 weeks reduce headache days for many people. Benefit often builds over the first two to three treatment cycles, so it is usually assessed after about 6 months.

What is a medication overuse headache?

It is a worsening of headaches caused by taking acute pain medicines too often, such as simple pain relievers on 15 or more days a month or triptans and combination medicines on 10 or more days a month. Reducing the overused medicine, often with a preventive, usually improves headaches.

Can chronic migraine go away?

It can improve substantially. With effective preventive treatment, reduced medication overuse and lifestyle changes, many people revert to having fewer than 15 headache days a month. Some people have long remissions, though migraine can return.