Medications used to treat migraine

Migraine can often be treated with paracetamol, ibuprofen or aspirin alone, or
with combination products containing them. There are also some non-prescription
medicines specifically licensed for the treatment of migraine. One such is a coformulation
of paracetamol, codeine and the antihistamine buclizine, included for
its antiemetic action. Other specific migraine treatments are reviewed below.



Sumatriptan
Sumatriptan is one of a group of compounds known as triptans. 
Mechanism of action
Triptans are 5HT1D-receptor agonists; they cause constriction of the cerebral arteries and counteract the cranial vasodilatation thought to be responsible for migraine attacks.
 Triptans are now established as a first-line treatment for migraine.
Sumatriptan is licensed for pharmacy sale for acute relief of migraine attacks,
with or without aura, in adults aged 18–65 years.
 warnings and contraindications
Treatment may not be supplied for prophylaxis or for patients who:
– are pregnant or breastfeeding
– have existing medical conditions, including cardiovascular conditions,
hypertension, peripheral vascular disease, liver or kidney disorders
– have any neurological condition or symptoms, including epilepsy
– are allergic to the drug
– are taking concurrent medication for migraine
Dosage
The dose is one 50 mg tablet, taken as soon as possible after the onset of an
attack. A second dose may be taken after 2 hours if migraine recurs. If there is
no response to the first tablet, a second tablet should not be taken for the same
attack. Maximum dosage is two tablets in 24 hours.

drug-drug interactions
Sumatriptan should be avoided by patients taking selective serotonin reuptake
inhibitors, monoamine oxidase inhibitors, moclobemide, St John’s wort
and other vasoconstrictor migraine treatments, especially ergotamine and
methysergide.



Ergot derivatives
Ergot derivatives are nonselective 5-HT1 agonists that have a wider spectrum of receptor affinities outside of the 5-HT1 system, including dopamine receptors. They can be used for the abortive treatment of moderately severe to severe migraine headache.

Ergotamine
Ergotamine counteracts episodic dilation of extracranial arteries and arterioles. It has partial agonist and/or antagonist activity against tryptaminergic, dopaminergic, and alpha-adrenergic receptors. Ergotamine causes constriction of peripheral and cranial blood vessels. The drug is available in a sublingual dosage form.

Dihydroergotamine
Therapeutic activity attributed to agonist effect at 5-HT-1D receptors, which includes vasoconstriction of intracranial blood vessels, or activation of 5-HT1D may inhibit proinflammatory neuropeptide release.


Isometheptene mucate
Isometheptene is a sympathomimetic, used in the treatment of migraine
and throbbing headache for its vasoconstrictor effect. It is combined with
paracetamol in one proprietary product.
The BNF has classified this product as ‘less suitable for
prescribing’ and states that other more effective treatments are available.


Prochlorperazine
Prochlorperazine is a phenothiazine derivative.
It is widely used on prescription for the treatment of vertigo and the prevention
of nausea and vomiting.
Prochlorperazine maleate buccal tablets are licensed for the non-prescription
treatment of nausea and vomiting associated with migraine.
The licensing conditions only permit supply if migraine has already been
diagnosed by a doctor, to adults of 18 years and over. It is contraindicated
in pregnant and breastfeeding women, and also in patients with impaired
hepatic function, narrow-angle glaucoma, prostatic hypertrophy, epilepsy or
Parkinson’s disease.