Chronic Migraine Headache

It is a type of headache that occurs on ≥15 days per month for more than 3 months, and has the features of migraine on at least 8 days per month


  • Sometimes referred to as transformed migraine.
  • It evolves from episodic migraine.
  • It is a type of headache that occurs on ≥15 days per month for more than 3 months, and has the features of migraine on at least 8 days per month.


  • Overall prevalence of chronic migraine among the general population is 0.9 to 2.2%.
  • Approximately 2.5% of patients with episodic migraine develop chronic migraine.
  • Chronic migraine is 2-3 times more common in women than men in the US.
  • 1.3% women and 0.5% men meet the criteria for chronic migraine in the US.


  • Exact mechanism is not known.
  • Associated with
    • Persistently increased cortical excitability
    • Central desensitization
    • Alteration in nociceptive signaling
    • Reduced cortical inhibition
  • Functional and structural abnormalities involving Periaqueductal Gray Matter can be associated with chronic migraine.
  • Impairment of cortical processing of sensory stimuli is also implicated.

Etiology and Risk Factors

  • The factors associated with transformation of episodic migraine into chronic migraine include
    • Obesity
    • Snoring
    • Sleep disorders
    • Excessive caffeine intake
    • Psychiatric disease; depression doubles the risk of developing chronic migraine.
    • High baseline headache frequency
    • Overuse of migraine abortive drugs
    • Major life changes
    • Head or neck injury
    • Cutaneous allodynia
    • Female sex
    • Comorbid pain disorders
    • Lower socioeconomic status

Diagnostic Criteria

International Classification of Headache Disorders (ICHD-3) Diagnostic Criteria for Chronic Migraine
Criteria A
  • Headache (tension-type-like and/or migraine-like)
  • 15 days per month for >3 months
  • and fulfilling criteria B and C
Criteria B
  • Occurring in a patient who has had at least five attacks fulfilling criteria Migraine without aura and/or Migraine with aura
Criteria C
  • On 8 days per month for >3 months, fulfilling any of the following:
    • Criteria C and D for Migraine without aura (refer to chapter; Types of headache)
    • Criteria B and C for Migraine with aura (refer to chapter; Types of headache)
    • Believed by the patient to be migraine at onset and relieved by a triptan or ergot derivative
Criteria D
  • Not better accounted for by another ICHD-3 diagnosis.
Source: Headache Classification Committee of the International Headache Society (IHS). The International Classification of Headache Disorders, 3rd edition (beta version). Cephalalgia. 2013 Jul;33(9):629-808. doi: 10.1177/0333102413485658. PMID: 23771276.

Differential Diagnosis

  • Hemicrania continua; daily, continuous, one-sided headache that is responsive to indomethacin.
  • Chronic tension-type headache
  • New daily persistent headache

Figure 1A: Classification per Headache Frequency

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Figure 1B: Classification per Duration of Individual Headaches

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Treatment and Management

  • The identification and treatment of the comorbid conditions improve the outcome in chronic migraine.
  • They include;
    • Sleep disorders
    • Chronic pain disorders
    • Depression
    • Anxiety
    • Cerebrovascular disorders
    • Cardiovascular disorders

Risk factor avoidance is important. This includes;

  • Weight loss with a regular exercise routine
  • Caffeine restriction
  • Decreased alcohol consumption
  • Relaxation and stress avoidance
  • Modifying the response to stressors
  • Good sleep hygiene
  • Avoiding overuse of migraine abortive drugs
  • Form and maintain a daily headache diary to help identify migraine triggers and avoid them.

Acute management

  • Should be initiated as soon as the headache starts. Should not be repeated more than 2 times per week. Includes;
    • NSAIDs
    • Dopamine antagonists
    • Triptans
    • Ergotamine
    • 📢
      DHE Protocol
      1. Diphenoxylate with Atropine (Oral)
        1. 1 Tablet given 4 times per day or as needed for diarrhea.
        2. Use for 3 days.
      1. Promethazine (Intravenous)
        1. 25mg Intravenous.
        2. Repeated 8 hourly.
        3. It should be given 10 minutes prior to DHE.
      1. DHE (Intravenous)
        1. Give 1mg intravenous.
        2. Repeated every 8 hours.
        3. Use for 3 days.
      1. Normal Saline
        1. Determined by the prescriber.

      Contraindicated in the following:
      • Heart disease
      • Stroke
      • Previous allergic reaction
      • Uncontrolled Hypertension
      • Renal Failure
      • Basilar Migraine
      • Hemiplegic Migraine
      • Within 24 hours of receiving triptan therapy


  • Migrainous infarction
  • Persistent aura without infarction
  • Migraine aura-triggered seizures


  • Many patients with chronic migraine revert back to episodes of migraine with the following;
    • Good compliance to migraine abortive drugs
    • Decreased headache frequency at baseline
    • Absence of cutaneous allodynia
    • Physical exercise
    • Withdrawal of overused migraine abortive drugs


  • Chronic Migraine is a debilitating condition.
  • Living with it is associated with significant unwanted negative stigma.
  • It causes immense financial and economic burden on the individual.
  • Decreases the workplace productivity and increases absence from work and school.
  • It is also associated with high disease burden, more severe psychiatric comorbidities and excessive use of healthcare facilities.

Further Reading

  • Chronic migraine. BMJ, 348(mar24 5), g1416–g1416. doi:10.1136/bmj.g1416


  1. Headache Classification Committee of the International Headache Society (IHS). The International Classification of Headache Disorders, 3rd edition (beta version). Cephalalgia. 2013 Jul;33(9):629-808. doi: 10.1177/0333102413485658. PMID: 23771276.
  1. Chronic Migraine: Epidemiology and Disease Burden. Current Pain and Headache Reports, 15(1), 70–78. doi:10.1007/s11916-010-0157-z
  1. Chronic Migraine: Epidemiology, Mechanisms, and Treatment. Chronic Headache. Springer, Cham.
  1. Your Resource for Headache Info | American Headache Society.
  1. Global prevalence of chronic migraine: A systematic review. Cephalalgia, 30(5), 599–609. doi:10.1111/j.1468-2982.2009.01941.x
  1. Spectrum of illness: Understanding biological patterns and relationships in chronic migraine. Neurology, 72(Issue 5, Supplement 1), S8–S13. doi:10.1212/wnl.0b013e31819749
  1. Chronic migraine. BMJ, 348(mar24 5), g1416–g1416. doi:10.1136/bmj.g1416
  1. The International Classification of Headache Disorders, 3rd edition (beta version). Cephalalgia, 33(9), 629–808. doi:10.1177/0333102413485658
  1. Chronic migraine: risk factors, mechanisms and treatment. Nature Reviews Neurology, 12(8), 455–464. doi:10.1038/nrneurol.2016.93)
  1. Treatment of acute migraine headache. Am Fam Physician. 2011 Feb 1;83(3):271-80. Erratum in: Am Fam Physician. 2011 Oct 1;84(7):738. PMID: 21302868.
  1. Chronic migraine: Symptoms, causes, treatments. (n.d.). Cleveland Clinic.
  1. Chronic migraine. (2021, June 3). The Migraine Trust.
  1. Calcitonin gene-related peptide (CGRP) receptor antagonists in the treatment of migraine. CNS drugs vol. 24,7 (2010): 539-48.
  1. Non Medication, Alternative, and Complementary Treatments for Migraine. Headache p. 796-806. August 2012, Vol.18, No.4. doi: 10.1212/01.CON.0000418643.24408.40

Preventive management


  • Beta-blockers
    • Propranolol
    • Timolol
    • Atenolol
    • Metoprolol
  • Anticonvulsants
    • Topiramate
    • Sodium Valproate
    • Gabapentin
  • Antidepressants
    • Nortriptyline
    • Amitriptyline
  • Calcium Channel Blocker
    • Flunarizine
  • Botox (Onabutolinum toxin A) injection
  • Calcitonin-gene related peptide, CGPR, Antagonists
    • Galcanezumab
    • Fremanezumab
    • Erenumab
  • Greater Occipital Nerve Blocks

Non pharmacological

  • Dietary supplements may help reduce migraine headaches. They include,
    • Coenzyme q10
    • Magnesium
    • Vitamin B-12
    • Butterbur (Coltsfoots)
    • Physical therapy
    • Behavioral therapy
    • Relaxation techniques
    • Biofeedback methods
    • Cognitive behavioral therapy
    • Massage
    • Acupuncture