Hemiplegic Migraine - The Basics

• Abortive and Pain Relief: Migraine-specific abortives, the triptans and ergotamines, are currently contraindicated in the treatment of Hemiplegic Migraine because of their vasoconstrictive properties and concerns about stroke. One small study was conducted, safely using triptans with patients with Hemiplegic Migraine, but more trials are needed before they're considered a safe option.² Since the triptans and ergotamines aren't options, other treatments such as NSAID's, antiemetics, and narcotic analgesics are generally used for relief of Hemiplegic Migraine.

• Preventive: Given the severity of the symptoms and the contraindication of abortive medications, preventive regimens are considered especially important in the treatment of Hemiplegic Migraine. As noted above the genes for FHM are mapped on chromosomes 1 and 19, These code for the calcium channel. "The mutant calcium channel does not open and close properly and cannot regulate the amount of calcium coming into the cell, so calcium influx and efflux regulation goes awry. This in turn leads to neurons firing too easily."³ For this reason, calcium channel blockers are sometimes especially effective preventive medications for FHM.

A Word of Caution:
Migraineurs with Hemiplegic Migraine should give special consideration to wearing some kind of medical identification at all times since an attack can lead to impaired consciousness and an inability to speak. Medical identification can save valuable time in an emergency and assure that proper treatment is received far more quickly.

Diagnostic Criteria from the International Headache Society⁴:

Familial hemiplegic migraine (FHM)
Description: Migraine with aura including motor weakness and at least one first- or second-degree relative has migraine aura including motor weakness.
Diagnostic criteria:

1. At least 2 attacks fulfilling criteria B and C

2. Aura consisting of fully reversible motor weakness and at least one of the following:

   1. fully reversible visual symptoms including positive features (e.g., flickering lights, spots or lines) and/or negative features (i.e., loss of vision

   2. fully reversible sensory symptoms including positive features (i.e., pins and needles) and/or negative features (i.e., numbness)

   3. fully reversible dysphasic speech disturbance

3. At least two of the following:

   1. at least one aura symptom develops gradually over ≥5 minutes and/or different aura symptoms occur in succession over ≥5 minutes

   2. each aura symptom lasts ≥5 minutes and <24 hours

   3. headache fulfilling criteria B–D for Migraine without aura begins during the aura or follows onset of aura within 60 minutes

4. D. At least one first- or second-degree relative has had attacks fulfilling these criteria A–E

Comments:
It may be difficult to distinguish weakness from sensory loss. New genetic data have allowed a more precise definition of FHM than previously. Specific genetic subtypes of 1.2.4 Familial hemiplegic migraine have been identified: in FHM1 there are mutations in the CACNA1A gene on chromosome 19, and in FHM2 mutations occur in the ATP1A2 gene on chromosome 1.

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