In the 14 included studies for preventive treatment there are only four studies rated “Class I” acc. to the American Academy of Neurology (AAN) Quality Criteria. Two of these four “Class I” studies had negative results.
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Summary of advisements for preventive treatment of cluster headache
Civamide
Direct evidence that civamide 100 µL is
effective in improving headache response
in CH. Nonserious adverse events: nasal
burning, lacrimation, pharyngitis,
rhinorrhea.
One randomized, controlled
clinical trial; AAN Class I
Level B: should be considered
for the prevention of CH
Suboccipital steroid injection
Direct evidence that long- and rapid-acting
steroids 2.5 mL are effective in improving
headache response in CH. Nonserious
adverse event: transient injection site pain.
One randomized, controlled
clinical trial; AAN Class I
Level B: should be considered
for the prevention of CH
Sodium valproate
Direct evidence that sodium valproate 500
mg is not effective in improving headache
response in CH. Adverse events not
reported.
One randomized, controlled
clinical trial; AAN Class I
Level B: not advised for the
prevention of CH
Sumatriptan
Direct evidence that sumatriptan 100 mg
is not effective in improving headache
response in CH. Nonserious adverse
events: nausea, vomiting, headache,
malaise.
One randomized, controlled
clinical trial; AAN Class I
Level B: not advised for the
prevention of CH
Melatonin
Evidence that melatonin 10 mg is effective
in improving headache response in CH.
Nonserious adverse events: none reported.
One randomized, controlled
clinical trial; AAN Class II
Level C: may be considered
for the prevention of CH
Verapamil
Evidence that verapamil 360 mg is
effective in improving headache response
in CH. Nonserious adverse events:
constipation, reduced blood pressure,
reduced heart rate.
Two randomized, controlled
clinical trials; 1 AAN Class II, 1 AAN Class III
Level C: may be considered
for the prevention of CH
Cimetidine/chlorpheniramine
Evidence that cimetidine 2,000 mg and
chlorpheniramine 20 mg are not effective
in improving headache response in CH.
Nonserious adverse events: transient,
erythematous skin rash. Other adverse
events not reported.
Two randomized, controlled
clinical trials; 2 AAN Class II
Level C: not advised for the
prevention of CH
Lithium
Evidence that lithium 900 mg is effective
in improving headache response in CH.
Nonserious adverse event: polyuria.
Two randomized, controlled
clinical trials; 2 AAN Class II
Level C: may be considered
for the prevention of CH
Misoprostol
Evidence that misoprostol 300 g is not
effective in improving headache response
in CH. Adverse events not reported.
One randomized, controlled
clinical trial; AAN Class II
Level C: not advised for the
prevention of CH
Oxygen
Evidence that 100% hyperbaric oxygen is
not effective in improving headache
response in CH. Adverse events not
reported.
One randomized, controlled
clinical trial; AAN Class II
Level C: not advised for the
prevention of CH
Capsaicin
Insufficient evidence that capsaicin is
effective in improving headache response
in CH. Adverse events not reported.
One randomized, controlled
clinical trial; AAN Class III
Level U: insufficient evidence
to advise for the prevention
of CH
Nitrate tolerance
Insufficient evidence that nitrate tolerance
via 5-ISMN 30 mg is effective in improving
headache response in CH. Adverse events
not reported.
One randomized, controlled
clinical trial; AAN Class III
Level U: insufficient evidence
to advise for the prevention
of CH
Prednisone
Insufficient evidence that prednisone 20
mg every other day is effective in
improving headache response in CH.
Adverse events not reported.
One randomized, controlled
clinical trial; AAN Class III
Level U: insufficient evidence
to advise for the prevention
of CH
Source: Francis GJ, Becker WJ, Pringsheim TM (August 2010). "Acute and preventive pharmacologic treatment of cluster headache". Neurology 75 (5): 463–73. Table 4.
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In the group for the acute abortive treatment of cluster headache there were eight studies rated “Class I” acc. to the American Academy of Neurology Quality Criteria.