Chronic Daily Headache

Chronic daily headache is defined as having headaches for 15 or more days per month for at least 3 months. It is important to note that this is a descriptive term, not a diagnosis. The approach to chronic daily headaches involves identifying whether any red flags are present and distinguishing between secondary and primary headache disorders.
==Algorithm Overview==
{{#mermaid:flowchart TD
 A[Chronic Daily Headache] --> B{Any RED FLAGS?}
 
 B -->|Yes| C[Consider secondary headache]
 B -->|No| D{Mean duration everyday}
 
 D -->|< 4h| E{Autonomic signs?}
 E -->|Yes| F[Chronic Paroxysmal HemicranialSUNAChronic Cluster]
 E -->|No| G[Hypnic HeadachePrimary stabbing headache]
 
 D -->|> 4h| H{Mandatory autonomic signs?}
 H -->|Yes| I[Hemicrania continua]
 H -->|No| J[Chronic MigraineNew daily persistent headacheTension Headache]
}}
== Secondary Headaches ==
=== Red Flags ===
When evaluating a patient with chronic daily headache, it is essential to screen for red flags. If any red flags are present, further evaluation for secondary headache disorders should be conducted. The SNNOOP10 mnemonic can help identify potential red flags, which are
=== Secondary Causes ===
Secondary headache disorders may arise from an identifiable underlying cause. When red flags are present, the following conditions should be considered:
* Medication-overuse headache
* Meningitis
* Systemic infections
* Obstructive sleep apnea
* Occipital neuralgia
* Post-stroke headache
* Post-traumatic headache
* Intracranial neoplasm
* Cerebral venous thrombosis
* High or low CSF pressure
* Cervicogenic headache
* Post-viral headache (including COVID-19-related headaches)
Diagnostic workup may include MRI, MRA, CT, CTA, CSF analysis, CRP, and ESR to identify or rule out secondary causes of headache.
If no red flags are present, primary headache disorders should be considered.
== Primary Headache Disorders ==
Primary headache disorders are classified based on the mean duration of headache per day and the presence of autonomic symptoms. The evaluation process distinguishes between headaches lasting less than 4 hours or more than 4 hours per day.
=== Headaches Lasting Less Than 4 Hours Per Day ===
When the mean duration of the headache is less than 4 hours, it is important to assess for autonomic symptoms such as:
* Nasal congestion and/or rhinorrhea.
* Conjunctival injection and/or lacrimation.
* Eyelid edema.
* Forehead and facial sweating.
* Miosis and/or ptosis.
==== Headaches < 4 hours with Autonomic Symptoms ====
If autonomic symptoms are present, the following conditions should be considered:
Chronic Paroxysmal Hemicrania
* At least 20 attacks fulfilling the following criteria:
** Severe unilateral orbital, supraorbital, or temporal pain lasting 2–30 minutes.
** Attack frequency is greater than or equal to 5 times per day.
* Must have at least one of the following symptoms ipsilateral to the headache:
** Conjunctival injection and/or lacrimation.
** Nasal congestion and/or rhinorrhea.
** Eyelid edema, forehead and facial sweating, miosis, or ptosis.
* The attacks occur for more than one year.
Short-Lasting Unilateral Neuralgiform Headache Attacks (SUNA)
* At least 20 attacks of unilateral headache lasting 1–600 seconds.
* The headache is accompanied by moderate or severe unilateral autonomic symptoms.
* At least one of the following is present ipsilateral to the headache:
** Conjunctival injection, lacrimation, nasal congestion, rhinorrhea, or eyelid edema.
* These headaches occur at least once a day.
Chronic Cluster Headache
* At least 5 attacks fulfilling the following criteria:
** Severe or very severe unilateral orbital, supraorbital, or temporal pain lasting 15–180 minutes.
** Attack frequency is between one every other day and up to 8 attacks per day.
* At least one of the following symptoms is present ipsilateral to the headache:
** Conjunctival injection, lacrimation, nasal congestion, rhinorrhea, eyelid edema, forehead and facial sweating, miosis, or ptosis.
* Attacks must be present for more than one year without remission, or with remissions lasting less than 1 month.
==== Headaches < 4 hours without Autonomic Symptoms ====
If autonomic symptoms are not present, the following conditions should be considered:
Hypnic Headache
* The headache must:
** Develop only during sleep and cause awakening.
** Occur on at least 10 days per month for more than 3 months.
** Last for at least 10 minutes and up to 4 hours after waking.
* There is no associated cranial autonomic symptomatology.
Primary Stabbing Headache
* This involves head pain occurring as a single stab or a series of stabs.
* The pain lasts for a few seconds and occurs without autonomic symptoms.
=== Headaches Lasting More Than 4 Hours Per Day ===
For headaches lasting more than 4 hours per day, it is essential to determine if autonomic symptoms are mandatory for diagnosis. 
==== Headaches > 4 hours with mandatory Autonomic Symptoms ====
If autonomic symptoms are necessary, the following disorder should be considered:
Hemicrania Continua
* The headache is unilateral and present for at least 3 months with exacerbations of moderate or greater intensity.
* At least one autonomic symptom or sign is present.
* The headache responds absolutely to therapeutic doses of indomethacin.
==== Headaches > 4 hours without mandatory Autonomic Symptoms ====
If autonomic symptoms are not required for diagnosis, the following conditions should be evaluated:
Chronic Migraine Disorder
* The headache must be present for more than 15 days per month.
* At least 8 of these headache days should have migraine features.
Chronic Tension-Type Headache Disorder
* This disorder features tension-type headache characteristics.
New Daily Persistent Headache
* The headache is persistent and distinct in onset, with clearly remembered timing.
* The pain becomes continuous and unremitting within 24 hours of onset.
* It must be present for more than 3 months.
==References==
For full diagnostic criteria, access the International Classification of Headache Disorders (ICHD-3).
Category:Headache Disorders
Category:Head and Jaw Conditions