Pathophysiology ,Diagnosis and Treatment of MIGRAINE Dr boyapati venupriya

Pathophysiology ,Diagnosis and Treatment of MIGRAINE

(Dr boyapati venupriya)

Migraine is defined as pulsating throbbing headache which increases in intensity on physical activity. It occurs typically on one side of the head accompanies with vision changes, sensitivity to light, and nausea.

                                              Types of Migraine :

There are two types of migraine headache:  

1)      Migraine with aura

2)      Migraine without aura

1) Migraine with aura: It is simply a physiological warning that occurs in individuals (patient) vision or other senses alerting the onset of a migraine. It can occur during or after migraine pain begins. Around 15% to 20% of those with migraines experience auras.

Patients who experience visual auras can see zig- zagging lines, lights look like stars or dots or even have a blind spot before a migraine starts. Besides visual auras, other senses are affected. Hearing auras can be experienced as ringing in ears before a migraine. Patients who experience smell auras will notice strange odors and taste, touch or simply sensing a “funny feeling” have also been reported as symptoms of migraine with aura. Whatever the type of aura symptoms will last less than one hour.

2)Migraine without aura: Around 85% of those with migraines experience migraine without aura. Patients experience all of the other features of a migraine attack, including intense pain on one/ other sides of the head, nausea, vomiting, and light/ sound sensitivity. Other signs include anxiety depression/ fatigue. it can last up to 72 hours before the headache pain. Other warning signs include feeling thirsty/sleepy/craving sweets.

 In general, it consists of three phases which include the prodrome phase, headache phase, and postdrome phase. Prodrome (pre headache) phase experience several hours/ even days before accompanied by food cravings, mood changes, muscle stiffness. During the headache phase, there will be quite debilitating pain in the entire body. In some patients between the prodrome phase and headache phase, they experience the aura phase. The postdrome phase goes with feeling hungover or tired.

                                       Triggers for migraine:

Most of the patients reported that migraine headache starts whenever they got triggered by some factors. The most common trigger factors are emotional stress, sleep disturbance, and dietary factors. Some studies found that lack of sleep and stress are the factors associated with migraine with aura. Environmental factors play a crucial role in patients having migraines without aura.

                                          Pathophysiology:

Migraines are regularly called as a threshold disorder connected with dysfunctional nociceptive processing. Several genetic, hormonal, and neurochemical factors work together and result in dysregulation of cortical and brainstem excitability.

A theory called cortical spreading depression is assumed to be related to migraine. CSD is depicted by a wave of significant cortical activation shadowed by sustained inhibition of activity. This excitability leads to cortical activation via neuronal and glial activation, which in the sequence is related to nociceptive activation and vascular changes comprising enhanced blood-brain barrier permeability. The vasodilation and neurogenic inflammation further increase activation of the sensory trigeminal fibres, continue the release of vasoactive peptides including CGRP, and modulate the transmission of pain impulses to the brain. The cortical activation extends to the brain stem via trigeminal pathways broaden boosting central sensitization. The central sensitization increases pain perception(migraine).

The added activity in the descending pain modulating neural networks sensitize an individual to be more susceptible to physiological and environmental elements that play a part in migraine attacks.

                                                      Diagnosis

To diagnose migraine a prior patient’s history must be collected to identify the possible triggers. Avoidance of triggers may result in better control of the disorder.

International classification of headache disorders gave criteria to diagnose migraine.

A.   At least 5 attacks 1 fulfilling criteria B-D

B.    Headache attacks lasting 4-72 hours (untreated/ unsuccessfully treated)

C.    Headache has at least 2 of the following 4 characteristics

1.unilateral location

2.pulsating quality

3.moderate/ severe pain intensity

4.aggravation by / causing avoidance of routine physical activity

      D. during headache at least one of the following

          1.nausea and/ vomiting

          2.photophobia and phonophobia

      E. not better accounted for by another ICHD-3 diagnosis

To rule out other co-morbidities orthopedic tests, cranial nerve examination, complete blood count, urinalysis and cranial magnetic resonance imaging will be recommended.

                                                     Treatment

Till now there are no standard treatments available. To treat a migraine patient's choice of medication based on individual bias and it is important to find out the underlying cause before selecting the drugs. Studies revealed that there are two approach considerations in treating migraine headaches.

·        Acute therapy or abortive therapy

·        Preventive therapy or prophylactic therapy

Acute therapy

Migraine medications act by changing the way cell function. Acute therapy reverse / at least stops the progression of a headache that has started.it is prescribed when the migraine starts. Medications include analgesics and triptans.

Acute medication for the treatment of migraine attacks: Limit intake to <10/15 days/ month.

·        Nausea / vomiting: Metoclopramide 10mg oral

                                Domperidone 10mg oral

·        Acute: Acetyl salicylic acid 1000mg

             Ibuprofen 200mg/400mg/600mg

             Metamizole 1000mg

             Diclofenac potassium 50mg/ 100mg

·        Combination analgesics: 2 tablets ASA 250mg/265mg+ Paracetamol/ Acetaminophen 200mg/ 265mg+ Caffeine 50mg/65mg

If the patient is contraindicated for NSAIDs:

Paracetamol / acetaminophen 1000mg oral / metamizole 1000mg oral

For moderate and severe migraine attacks and lack of response to analgesics:

Triptan therapy:

Fast onset of action: Sumatriptan 6mg sc

                                  Eletriptan 20mg/40mg/80mg oral

                                  Rizatriptan 5mg/ 10mg oral

                                  Zolmitriptan 5mg nasal spray

Moderately fast onset and longer-lasting effect:

                                  Sumatriptan 50mg/ 100mg oral

                                  Zolmitriptan 2.5mg / 5mg oral

                                  Almotriptan 12.5 mg oral

Slow onset with the long-lasting duration of action:

                                 Naratriptan 2.5 mg oral

                                 Frovatrpitan 2.5 mg oral

If monotherapy is insufficient: Triptan + NSAIDS (naproxen 1000mg)

For recurrence of headache:

Re administration of a triptan after at least 2 hours.

Initial combination therapy: Triptan+ long-lasting NSAID (naproxen)

Emergency medication for migraine attacks:

                                 Metoclopramide 10mg IV

                                 Lysine acetyl salicylate 1000mg IV

                                 Sumatriptan 6mg sc

Preventive therapy:

Preventive therapy will be prescribed in the absence of a headache to reduce the frequency and severity of the migraine attack, make acute attacks more responsive to abortive therapy. Also, improve the patient’s quality of life.

Medications include beta-blockers, anti-depressants, calcium channel antagonists, antiepileptics.

Beta-blockers:

Atenolol: 50-200mg

Metoprolol: 100-200mg

Nadolol: 20-160mg

Propranolol: 40-240mg

Timolol: 20-60mg

Anti-depressants:

Amitriptyline: 10-200mg

Doxepin: 10-200mg

Nortriptyline: 10-150mg

Calcium channel antagonists:

Verapamil: 120-480mg

Flunarizine: 5-10mg

Anti-epileptics:

Carbamazepine: 600-1200mg

Gabapentin: 600-3600mg

Topiramate: 50-200mg

Valproate: 500-2000mg

 By  Dr Boyapati Venupriya