Preventer therapy principles
There is no way to predict response to migraine prevention therapies but in general
each individual therapy will work in 5 out of 10 patients to reduce migraine frequency
and severity by half. Scottish Headache Guidelines i.e. SIGN107 recommends first
line migraine prevention therapy is Propranolol, second choice Tricyclic and third
choice anti-epileptic such as Topiramate or Valproate. NICE headache guidelines
recommend first line migraine prevention therapy is Propranolol or Topiramate,
second line, Gabapentin or acupuncture. Acupuncture of course is not available on
the NHS for headache.
Anti epileptics
Topiramate is an anti epileptic that is licensed for migraine and can be initiated in
primary care. SIGN guidelines place it as a second line treatment but NICE
guidelines place it as a first line treatment. The starting dose is 25mgs at night and it
is titrated by 25mg every 1-2 weeks depending on tolerability to a dose of 50mgs
twice a day. Common side effects are pins and needles, nausea, minor weight loss,
sleepiness. Less common side effects are cognitive impairment, irritability, glaucoma
and significant weight loss. Topiramate can be very helpful in patient with migraine
with 2 patients out of 10 achieving significant headache reduction and 6 patients out
of 10 getting a partial response. Two patients out of 10 will have to stop therapy due
to either side-effects or lack of efficacy. Women of child bearing age have to effective
contraception.
Gabapentin is an anti epileptic. This is more commonly being used for migraine as
well as neuropathic pain. It is a second line treatment in the NICE guidelines.
Starting dose is 100mgs 3 times a day, titrating up to 400mgs 3 times a day.
Women of childbearing age have to have effective contraception. Side-effects can
affect between 1-10 and 1-100 patients are gastro-intestinal upset, weight gain,
sedation, dizziness and headache. Side-effects that affect between 1-100 and 11000 patients are palpitations, hair loss and hallucinations. Woman of childbearing
age have to have effective contraception.
Pregabalin is an anti epileptic and is sometimes used in migraine. As well as being
helpful for migraine it is licensed for neuropathic pain and generalised anxiety
disorder. The starting dose would be 25mgs twice a day which can be titrated up by
25mgs twice a day every week aiming for a dose of between 300-600mgs in divided
doses. Potential side-effects are: for between I in 10 to 1 in 100 patients
gastrointestinal upset such as constipation, nausea or vomiting and dry mouth. For
between 1in 100 and 1 in 1000 patients palpitations, hallucinations and hair loss.
Woman of childbearing age have to have effective contraception.
Valproate is an anti epileptic. Starting dose is 200mgs twice a day titrated up every
2 weeks to a dose of 600-1000mgs twice a day. Side-effects between 1-10 and 1100 patients are diarrhoea, nausea, weight gain and temporary hair loss. Sideeffects in 1-100 to 1-1000 patients are increased alertness and tremor. Valproate
usually has a very good effect on mood and is generally well tolerated. Woman of
childbearing age have to have effective contraception.
Beta Blocker. Propranolol is the standard first line treatment in both the SIGN and
the NICE guidelines. Starting dose is 20mgs twice a day and this is titrated up to
160-240mgs in 2-3 divided doses. Side effects in 1-10 and 1-100 patients are
gastro-intestinal upset, cold hands and feet, fatigue, headache, disturbed sleep, low
blood pressure and impotence. Less common side-effects between 1-100 and 11000 patients are rashes and dry eyes.
Tricyclics
Amitriptyline and Nortriptyline can help headache. These are old medicines that are
rarely used as anti-depressants. They are used in neuropathic pain such as diabetic
pain and shingles and can be helpful in headache. The starting dose is 10mgs at
night which is titrated up aiming for a dose of anything between 10 – 100mgs
depending on efficacy and tolerability. Side effects can include sedation and a dry
mouth. They are more likely to give side effects in patients over 65 years age and
should be avoided. Nortriptyline is generally less sedating than Amitriptyline.
Indometacin
In any patient with chronic headache that is strictly unilateral hemicrania continua
has to be excluded. This is a rare headache and the majority of patients will have
chronic migraine. Hemicrania continua is universally responsive to indometacin, an
old non steroidal anti inflammatory. The diagnostic regime is to titrate the dose ever
week until the headache settles. If the maximum daily dose of 225 mg does not work
hemicrania continua is very unlikely. The dosing regime is
 Week one 25mgs 3 times a day
 Week two
50mgs 3 times a day
 Week three 75mgs 3 times a day
Patients should be warned about gastric side effects and be given PPI cover.
Indometacin can occasionally cause sedation.
Candesartan: This is an ARB blood pressure tablet used in Scandinavia due to its
usually reasonably well tolerated side-effect profile. It can occasionally cause low
blood pressure and making people a bit dizzy and it can cause a dry cough. In my
experience it can reduce headache intensity but very often not headache frequency.
Starting dose is 2 mg titrating up to 16mg. Renal function needs monitored.
Pizotifen is an old fashioned migraine treatment that works better in children and
teenagers. It can be helpful in patients with dizziness as part of migraine. It can
make people sedated so it is taken at night time and it can cause increased appetite.
However in some adults it can be very effective.
Venlafaxine: Venlafaxine is an SNRI anti-depressant but has some evidence in
migraine. Side effects to watch out for would include gastric upset, raised blood
pressure, dizziness, anxiety, palpitations, sweating and headache. The starting dose
is 75mgs daily titrated up to 150mgs if need be. If it is to be stopped it should be
withdrawn gradually to prevent discontinuation syndrome.