AUTHOR AND EDITOR INFORMATION

Section 1 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

INTRODUCTION

Section 2 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Background

Chronic paroxysmal hemicrania (CPH) is also known as Sjaastad syndrome. It was first described in 1974 by Sjaastad and Dale.¹ In 1976, the term CPH was proposed by Sjaastad on the basis of the first 2 patients, who had daily (ie, chronic), solitary, limited attacks (ie, paroxysmal) of unilateral headache that did not shift sides (ie, hemicrania).² CPH, which has been included in the International Headache Society (IHS) classification system since 1988, is much less common than cluster headache (CH).

The short-lasting primary headache syndromes may be divided into (1) headaches with autonomic activation and (2) headaches without autonomic activation. Headaches with autonomic activation include chronic and episodic paroxysmal hemicrania, CH, and short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT syndrome).

Pathophysiology

The mechanisms responsible for the pain in CPH remain unknown. Discussion of important features, such as unilateral intense headache, autonomic abnormalities, and effectiveness of indomethacin, may help in understanding the pathogenesis.³

The release of both trigeminal and parasympathetic neuropeptides during headache has been described.⁴ Activation of the ipsilateral trigeminovascular system may explain sudden unilateral headache and may lead to miosis, increased intraocular pressure (IOP), and other autonomic abnormalities.

Increased sweating and decreased salivation during attacks and inhibition of increased IOP by an alpha-blocking agent or stellate ganglion blockade suggest sympathetic involvement.

Increased tearing, nasal secretion, and miosis may be due to parasympathetic stimulation. Trigeminoparasympathetic activation during CPH attack has been suggested; increases in vasoactive intestinal peptide (ie, parasympathetic peptide) level have been reported. Levels of calcitonin gene-related peptide also are reported to be high during CPH attacks.

Pain and pressure threshold, nociceptive flexion reflex, and blink and corneal reflexes have been studied in patients with CPH. The corneal reflex thresholds have been found to be decreased bilaterally during CPH attacks. Increases in corneal temperature on the symptomatic side also have been reported; this finding may be due to increased ocular blood flow.

The effectiveness of indomethacin in CPH may be due partly to reduction of intracranial blood flow (via a nonprostaglandin mechanism) and partly to its anti-inflammatory effects.

These findings may indicate a primary central mechanism and a secondary involvement of peripheral factors, affecting both the sympathetic and parasympathetic systems.

Frequency

United States

CPH is a rare syndrome, but the number of diagnosed cases is increasing. The prevalence of CPH is not known, but the relative frequency compared with CH is reported to be approximately 1-3% (Antonaci, 1989).

International

Many cases of CPH have been described throughout the world, in different races and different countries, including Australia, Czech Republic, Slovakia, Denmark, Italy, France, Mexico, Canada, Sweden, Germany, Poland, India, Spain, Brazil, South Africa, Norway, New Zealand, the United Kingdom, and the United States.

Mortality/Morbidity

Mortality rate and morbidity of CPH have not been reported, although the therapy of choice, indomethacin, is known to be associated with the risk of bleeding.

Race

CPH is not known to occur preferentially in any race. CPH has been described in Caucasians and black South Africans.

Sex

In the past, because of female preponderance, CPH was considered a disease of women. However, CPH has been reported in increasing numbers of men. A study conducted in 1979 reported a female-to-male ratio of 7:1, but a review of 84 patients in 1989 reported a female-to-male ratio of 2.3:1.

Age

CPH can occur at any age; mean age of onset is 34 years.⁵ The youngest patient described in the literature was aged 6 years and the oldest was aged 81 years.^{6, 7} In one report, CPH beginning at age 3 years was described; however, it may have been related to ipsilateral occipital hemorrhagic infarction.⁸

CLINICAL

Section 3 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

History

The pain is unilateral, always affects the same side, and is generally oculofrontotemporal in location. The literature does contain reports of a few unusual cases, for example, patients with bilateral symptoms and possible shift in the side of the headache when the CPH progresses from the nonchronic to the chronic stage.

• The pain is usually most severe in the oculotemporal area, the forehead, and above or behind the ear. Occasionally, pain can radiate and involve the ipsilateral shoulder, arm, and neck.
• Headache can appear at any time in patients with CPH, in contrast to CH in which the headache usually occurs at night.
• During severe attacks, excruciating pain with throbbing, boring, pulsating, or clawlike character has been described. In contrast to patients with CH, patients with CPH usually sit quietly or may curl up in bed between attacks.
• The attack frequency usually is 10-20 attacks per day and may range from 2-40 attacks per day. Attacks usually last 2-25 minutes, but they may last as long as 60 minutes. In one prospective study, mean attack duration was 13 minutes (range 3-46 min). In a retrospective study, the mean duration of attacks was 21 minutes (range 2-120 min).
• CPH can be triggered by various stimuli, including neck movement, external pressure to neck, or other factors.
• CPH attacks are accompanied by autonomic symptoms, mostly on the same side as the pain, such as red eyes, tearing, nasal congestion, and sometimes rhinorrhea. Occasionally, photophobia may be present, but gastrointestinal symptoms are very rare.
• Recognizing the various stages and different patterns of CPH is important. For example, during severe frequent attacks, patients may describe a constant headache or persisting tenderness on the symptomatic side.
• IHS diagnostic criteria for CPH include the following (slightly modified from the Headache Classification Committee, 1988):
• • 1. At least 50 attacks fulfilling the criteria mentioned below in 2-5.
  • 2. Attacks of severe unilateral orbital, supraorbital, and/or temporal pain always on the same side lasting 2-45 minutes
  • 3. Attack frequency more than 5 per day for more than half of the time (periods with lower frequency may occur)
  • 4. Pain associated with at least one of the following signs/symptoms on the symptomatic side:
    • Conjunctival injection
    • Lacrimation
    • Nasal congestion
    • Rhinorrhea
    • Ptosis
    • Eyelid edema
  • 5. Absolute effectiveness of indomethacin (150 mg/d or less)
  • At least one of the following:
    • History, physical, and neurologic examination findings do not suggest any of several disorders that include organic headaches, headaches associated with drug withdrawal, metabolic disorders, and other conditions.
    • History and/or physical and/or neurologic examination findings do suggest such a disorder, but it is ruled out by appropriate investigations.
    • Such a disorder is present, but CPH does not occur for the first time in close relation to the disorder.
• CPH may be present in nonchronic or chronic form, which is 4 times more common.
• • Nonchronic attacks are similar to chronic attacks but may be less severe and less frequent.
  • The term pre-CPH stage or prechronic was preferred initially on the basis of the assumption that all patients would develop chronic symptoms. However, approximately 20% of patients appear to remain in the nonchronic stage for long periods.
  • Before development of chronic symptoms, many patients (42%) pass through a nonchronic stage with attacks separated by intervals of complete remission.
  • Dividing CPH into unremitting and remitting forms may be appropriate. The unremitting form is the chronic form, which either is unremitting from the onset or evolved from the remitting form.

Physical

• The pain is severe, and attacks are associated with autonomic features, such as lacrimation (62%), conjunctival injection (36%), ipsilateral nasal congestion (42%), rhinorrhea (36%), and eyelid edema (33%).
• • Lacrimation may occur bilaterally but is always more marked on the symptomatic side.
  • Occasionally, mild ipsilateral miosis may be observed during attacks.
• Patients with CPH who had dissociation in pain and autonomic features also have been described.
• No definite evidence points to a Hornerlike syndrome, such as that described in CH, but mild miosis and eyelid edema that may mimic ptosis may be observed.
• Forehead sweating may increase on the ipsilateral side, and patients with generalized sweating have been reported.
• The coexistence of CPH and trigeminal neuralgia is called CPH-tic syndrome; many cases of this syndrome have been reported.
• Simultaneous occurrence of ipsilateral CH and migraine headache in patients with CPH also has been reported.
• Perform a careful physical examination to evaluate pathological secondary headache.

Causes

No definite cause is known.

• The past medical history in patients with CPH is usually unremarkable. History of head or neck trauma is reported in about 20% of cases, but these findings are similar to CH or migraine.
• Occasionally, attacks may be provoked mechanically by bending or rotating the head and by applying external pressure against the transverse processes of C4-C5, C2 root, or the greater occipital nerve.
• No familial disposition is known for CPH; families of affected individuals do not have higher incidences of CH or migraine than the general population.

DIFFERENTIALS

Section 4 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Other Problems to be Considered

Differential diagnosis should include other headaches with major autonomic features (eg, SUNCT syndrome) and persistent headaches with milder autonomic features (eg, hemicrania continua [HC]).

Several paroxysmal indomethacin-responsive headache syndromes have been described, including HC, jabs-and-jolts syndrome, icepick headache, hypnic headache syndrome, benign cough headache syndrome, benign exertional headache, coital headache, and thunderclap headache.

Cervicogenic headache, facial neuralgia, and other rare disorders, such as the red ear syndrome, also are considered in the differential diagnosis.

Simultaneous occurrences of CPH and other disorders, including CH, trigeminal neuralgia (CPH-tic syndrome), and migraine, also have been reported. The crucial factor in the differential diagnosis is the absolute response to indomethacin.

The trigeminal-autonomic cephalgias include CH and paroxysmal hemicranias in which head pain and cranial autonomic symptoms are prominent. CH is the most important differential diagnosis.

CH has male preponderance, unlike CPH, which is more common in females. In CPH, frequency of attacks is higher, usually more than 15 in 24 hours, whereas CH has an attack frequency of 1-4 (maximum 8) in 24 hours. The duration of headaches is shorter in CPH (2-25 min) than in CH (15-60 min).
Finally, CPH can be distinguished by its response to indomethacin therapy, which is not seen in CH.

HC is a rare disorder characterized by continuous, unilateral, indomethacin-responsive hemicrania of moderate severity. These headaches last from minutes to several days and sometimes are associated with autonomic features. A noncontinuous form also has been described.

The SUNCT syndrome is a distinctive rare condition with male preponderance characterized by less severe pain but marked autonomic activation during attacks. The pain, usually in the frontal and periocular area, is intractable to medications, including indomethacin.

Recently, a unique, stereotypical, episodic headache disorder marked by long-lasting autonomic symptoms with associated hemicrania (LASH) has been reported. The autonomic symptoms clearly overshadowed the headache as the major component of the syndrome. Both types of symptoms responded to indomethacin.

Other disorders that may mimic CPH include infarcts, arteriovenous malformation, brain tumor (eg, frontal lobe tumor, meningioma of the roof of the cavernous sinus, pathological process in the region of the cavernous sinus, gangliocytoma near sella turcica, parasellar pituitary microadenoma), maxillary cyst, collagen vascular disorders, cervical radiculopathy, disk herniation, and carotidynia.

WORKUP

Section 5 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Lab Studies

• Perform lab studies to evaluate structural, metabolic, and other secondary causes of headache and facial pain.
• Baseline routine blood tests may be needed to exclude contraindications to certain drugs and to avoid complications from long-term use of various medications.

Imaging Studies

• CT scan, or preferably MRI, of the brain may be needed to rule out structural pathology.
• Findings of neuroimaging studies, including MRI, are usually normal in patients with CPH.
• Consider MR angiogram or arteriogram, if necessary, for atypical presentations.
• Electroencephalography, brain mapping, and other radiologic studies are not required for patients with typical presentations.

Other Tests

• Indotest (indomethacin 50 mg IM test dose) may be a useful tool in assessment of unilateral headache. The diagnosis of CPH is extremely important because it may imply lifelong treatment with a potentially noxious drug. Perform indotest in a standardized manner.
• No characteristic electrocardiographic patterns were found during attacks, but marked variations in heart rate and rhythm abnormalities, including bradycardia, sinoatrial block, bundle branch block with episodes of atrial fibrillation, and multiple extrasystoles, have been observed.
• Orbital phlebography may be abnormal in some patients, but the significance of this finding has not been established.
• In one study of 3 patients with CPH, a slightly lower cerebral vasomotor reactivity was observed in the medial and posterior cerebral arteries on both sides and in the anterior cerebral artery on the symptomatic side than in healthy subjects. These observations may imply an abnormal vascular reactivity in CPH.
• As compared to CH, CPH attacks did not demonstrate any changes in visually evoked event-related potentials (ERPs), latencies, and amplitudes.⁹
• Perform ophthalmic evaluation, if needed, to assess ocular pathology such as glaucoma or orbital pseudotumor.

Procedures

• Consider lumbar puncture, if necessary, for atypical presentations.

TREATMENT

Section 6 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Medical Care

• The treatment of choice for CPH is indomethacin, which has an absolute effect on the symptoms. Both episodic CH and CPH respond well to indomethacin.
• Other medications that may provide relief include salicylates (aspirin), naproxen, prednisone, celecoxib, piroxicam, acetazolamide, and ergotamine. One prospective open trial conducted with 10 patients experiencing CPH suggests that acetylsalicylic acid (and probably naproxen and diclofenac) and verapamil (for prophylaxis) are the most effective second-line drugs. In another report, two teenaged girls who demonstrated dramatic, yet incomplete, improvement with indomethacin had nearly complete relief with verapamil monotherapy (Shabbir, 1994).
• The efficacy of sumatriptan in CPH is still controversial (Dahlof, 1993; Hannerz and Jogestrand, 1993; Evers, 1996; Pascual, 1998).
• Oxygen, lithium, carbamazepine, and other anticonvulsants are ineffective in patients with CPH.
• Anesthetic blockade of the occipital nerves and supraorbital nerve have not provided significant relief. Occipital nerve blockade helps in distinguishing CPH and HC from cervicogenic headache. Supraorbital nerve blockade may help in distinguishing HC and supraorbital nerve neuralgia (in which nerve block is markedly effective).
• Reliable evidence of efficacy of chiropractic manipulation, acupuncture, or surgical management in the treatment of CPH does not exist.

Consultations

Ophthalmologist - To evaluate ocular pathology such as glaucoma or orbital pseudotumor

MEDICATION

Section 7 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Drug of choice in the treatment of CPH is indomethacin. When a patient experiences frequent unilateral headaches (ie, >4 attacks in 24 h), a drug trial with indomethacin should be considered. The dose of indomethacin should be increased to at least 150 mg/d for 3-4 d. Beneficial effect is seen usually within 48 h, but may take as long as 5 d. In one study, indomethacin effect was complete within 24 h in most patients, and frequently the effect was seen within 8 h. Maintenance dosage is usually 25-100 mg/d but may range from 12.5-300 mg/d. After discontinuation of medication, symptoms usually reappear within 12 h to a few days. However, long remission periods lasting years have been described.

About 10% of patients may experience adverse effects of indomethacin, including dyspepsia, nausea, vomiting, vertigo, gastric bleeding, purpura, and other conditions. To prevent gastric adverse effects, antacids, misoprostol, or an H2 antagonist or proton pump inhibitor may be coadministered when indomethacin is being used for longer periods. An indomethacin suppository is another option for gastric intolerance or when a higher dose (eg, 300 mg/d) is needed.

A recent article suggests that topiramate could be helpful as a preventive agent.

Drug Category: Nonsteroidal anti-inflammatory drugs (NSAIDs)

These agents have analgesic, anti-inflammatory, and antipyretic activities. Their mechanism of action is not known, but they may inhibit cyclooxygenase activity and prostaglandin synthesis. Other mechanisms may exist as well, such as inhibition of leukotriene synthesis, lysosomal enzyme release, lipoxygenase activity, neutrophil aggregation, and various cell-membrane functions.

Drug Category: Calcium channel blockers

These agents inhibit calcium ions from entering slow channels, select voltage-sensitive areas, or vascular smooth muscle. Verapamil may be an effective calcium channel blocker for prophylaxis of CPH.

Drug Category: Corticosteroids

These agents may be effective in treatment of CPH. Pain relief may occur via inhibition of prostaglandin synthesis.

Drug Category: Anticonvulsants

Agents with state-dependent sodium channel–blocking action and inhibitory activity of neurotransmitter GABA may have prophylactic effects on CPH.

FOLLOW-UP

Section 8 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Complications

• Take precautions to prevent serious gastrointestinal and renal complications secondary to long-term use of indomethacin.

Prognosis

• In the nonremitting stage of CPH, patients may need lifelong therapy, possibly with smaller doses of indomethacin.
• Long-lasting remission periods usually reflect a nonchronic stage, but they may occur in patients with established chronic disease.
• In chronic cases, recurrence of attacks after a drug-free period of 1.5 years has been reported.

MISCELLANEOUS

Section 9 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

Medical/Legal Pitfalls

• Appropriate studies should be performed to exclude secondary headache disorders.

Special Concerns

• CPH attacks have been reported to improve during pregnancy; however, they recur after delivery.
• Menstruation may have either a positive or negative effect on attacks.
• Birth control pills do not seem to influence attack frequency.
• Reliable data do not exist regarding the effects of menopause on CPH.

REFERENCES

Section 10 of 10

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• References

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Article Last Updated: Nov 28, 2007