Introduction to Migraine

What is a Migraine
The pathophysiology of migraine is not well understood and there are various theories to explain the neurological symptoms and headache symptoms. However none of them explain how a migraine is triggered, making it difficult to develop treatments.
Medication Categories
The treatment of migraine can be split into medications used in an acute attack and as propyhlaxis.
Acute Attack
Initially try simple analgesics such as paracetamol, aspirin or NSAIDs. Simple analgesics; If these are not effective, triptans can also be used.

Triptans - 5-HT1D receptor agonists - there are a variety of types and administration routes - some can be given intranasally or by subcutaneous injection as well as orally. Please see Triptan section for further information.

Patients with a migraine can have delayed gastric emptying as well as the nausea and vomiting that can accompany migraines. This may lead to analgesics / triptans being poorly absorbed. Patients may require an antiemetic to stop the nausea associated with migraine and aid absorption of the analgesic. Be aware that there are other ways of administering therapy e.g. as a suppository if the patient is unable to take it orally. Patients should be aware that if they use analgesics regularly they are at risk of developing medication overuse headache.
Prophylaxis
Prophylaxis should be considered in patients with frequent migraines which interfere with their daily lives, in the failure of acute treatments and in uncommon forms of migraine e.g. basilar migraine or hemiplegic migraine. The medications recommended to reduce migraine frequency come from various classes of drugs, further supporting the fact that the pathogenesis of migraine remains uncertain.

The type of prophylactic will be based on a patient's co morbidities and patients should be given a low dose and titrated up. They should have a trial of approximately 2 months following the dose titration to actively assess its effectiveness.

Beta-blocker - Propanolol is the favoured beta blocker, but Atenolol, Nadolol and Metoprolol can also be considered. Avoid in patients with asthma, peripheral vascular disease and depression.

Pizotifen - 5-HT receptor antagonist. Studies have shown that it does reduce the frequency of migraine compared to placebo, however the SIGN guidelines state that it is of limited value on migraine prophylaxis.

Antidepressants - Amitriptyline is the most commonly prescribed. Venlafaxine has also been found to be effective but SSRIs are not.

Antiepileptic medications - Topiramate, Sodium Valproate and Gabapentin can be considered
References
Hauser S. Harrison's Neurology in General Practice. McGraw-Hill Companies Inc. 2006.

Rang H.P, Dale M.M, Ritter J.M, Flower R.J. Rang and Dale's Pharmacology. 6th Edition

Sign Guidelines 107: Diagnosis and Management of Headaches in Adults