Migraine is a common type of headache that occurs
with symptoms such as nausea, vomiting, loss of appetite, food intolerance or
sensitivity to light (photophobia). Many people experience a throbbing pain on
one side of the head.
An aura, which could be a warning sign of
migraine, includes vision disturbances and is experienced by some people before
migraine sets in.
Migraine treatment aims to stop or prevent the progression
of a headache or reverse a headache that has started. Preventive treatment,
which is given even in the absence of a headache, aims to reduce the frequency
and severity of the migraine attack and also improves the patient's quality of
In 2012, Quality Standards
Subcommittee of the American Academy of Neurology (AAN) and the American
Headache Society (AHS) classified the medications used for migraine into seven
categories (levels A, B, C, U, A negative, B negative, C negative) based on
their efficacy for migraine prophylaxis. Apart from the pharmacologic agents and complementary therapies, the
guidelines also addressed new therapies for the short-term prevention of
LEVEL A PHARMACOLOGIC AGENTS:
The efficacy of these drugs in preventing migraine
have been established in more than two class I clinical trials. These are:
Drugs: Divalproex Sodium and Sodium Valproate, Topiramate:
drugs are thought to prevent migraine by increasing levels of gamma amino
butyric acid (GABA) in the brain; GABA is a neurotransmitter which suppresses
the abnormal electrical activity in the brain. Results of a clinical trial
showed that divalproex sodium XR (extended release) is efficacious when used as
a single drug to prevent migraine. Another clinical trial showed that topiramate
achieved a higher mean reduction in frequency, intensity, and duration of
headaches as compared to propranolol; however high-dose topiramate could cause
significant adverse reactions such as fatigue, memory lapse, taste disturbance,
weight loss, and paresthesia.
Though it is not very clear how they prevent migraine,
beta blockers such as propranolol
are now commonly used for
migraine. The efficacy of propranolol has been well established in clinical
trials and is one of the most commonly prescribed beta blocker for migraine
prevention. In a study comparing metoprolol and aspirin, it was found that
metoprolol was more effective than aspirin in reducing the frequency of
migraine, but the aspirin group experienced lesser adverse effects.
Triptans are recommended for moderate to severe migraine
or failure to respond to other acute migraine treatments. Frovatriptan
selective serotonin receptor agonist, has a long-lasting effect, which provides
the opportunity to use it as preventive treatment in menstrually associated
migraine (MAM). In a study, it was shown that frovatriptan when given for 6
days during the perimenstrual period was highly effective for prevention as
well as reduction in severity of MAM.
LEVEL B PHARMACOLOGIC AGENTS:
These drugs are probably effective in preventing
migraine. Besides the antidepressants venlafaxine and amitriptyline and the
triptans naratriptan and zolmitriptan, this group also included the beta
blockers atenolol and nadolol.
Studies have shown that venlafaxine
achieved reductions in
migraine frequency, intensity, and duration. It was shown that although both
drugs are effective, venlafaxine XR was much more favorable and tolerable than
A study on the efficacy of naratriptan for short-term
prevention of MAM during perimenstrual periods concluded that naratriptan 1 mg
twice daily was efficacious for preventive treatment of MAM and exhibited a
well-tolerated adverse effect profile. Studies have also shown zolmitriptan to
be superior to placebo in the prophylactic treatment of MAM.
LEVEL C PHARMACOLOGIC AGENTS:
These include drugs such as lisinopril, candesartan
clonidine, guanfacine, carbamazepine, pindolol and nebivolol. These drugs are
possibly effective in the prevention of migraine.
LEVEL U PHARMACOLOGIC AGENTS:
This group includes drugs such as
gabapentin, picotamide, warfarin and acenocoumarol, fluoxetine, fluvoxamine,
protriptyline, bisoprolol, nifedipine, nicardipine, nimodipine, verapamil,
acetazolamide and cyclandelate. There is inadequate or conflicting data to
support or refute the claim that these drugs are useful in the treatment of
NEGATIVE PHARMACOLOGIC AGENTS:
These drugs are possibly or probably ineffective in
the prevention of migraine.
study comparing the efficacy of low dose topiramate and lamotrigine found that
topiramate was superior to placebo and lamotrigine, and lamotrigine was
ineffective versus placebo and topiramate for migraine prophylaxis. However,
the researchers said that lamotrigine's efficacy should not be automatically
discounted, because the study had certain limitations such as the duration of
the study was short and the statistical analysis power was insufficient.
There has been conflicting reports on aspirin on whether it
is efficacious for migraine prophylaxis; therefore this agent remains a level U
Level A Complementary
The extract of†Petasites hybridus
plant, also known as
butterbur, is a powerful migraine-preventive agent.Butterbur's
headache-preventive capabilities are mainly due to its anti-inflammatory and
muscle-relaxant effects. In a double-blind randomized study, Petasites
75 mg twice daily was shown to reduce the frequency of migraine attacks.
Level B Complementary
Magnesium, Riboflavin, and Feverfew:
herb feverfew (Tanacetum parthenium
has been used for many years for headache, migraine and fever.
Magnesium is a mineral found mainly in green
leafy vegetables, whole grains etc. Several studies have shown positive results
for the use of magnesium in migraine.
Riboflavin, in high doses, has also been shown to
help migraine sufferers.
Individual clinical trials have supported the
efficacy of these complementary therapies when used alone; thus these agents
could be used as an adjunctive therapy to other proven pharmacologic agents.
Pharmacologic and Complementary
Therapy for Migraine Prophylaxis; Amne et al; US Pharmacist 2013