Antimigraine drugs

Clinical presentation and pathogenesis of migraine

Migraine is a chronic condition manifested by periodic attacks of excruciating headache. The pain is typically unilateral and characterized by pronounced pulsation. Without medical intervention, the duration of a single attack can range from 4 to 72 hours. The condition can trouble the patient for many years, with the frequency of exacerbations averaging from one to four times a month.

In addition to the pain syndrome itself, the clinical picture is often complicated by associated symptoms. These include severe nausea progressing to vomiting, as well as various visual and auditory disturbances.

In terms of etiology and pathogenesis, the exact nature of this disease is not fully understood. However, the main medical theory links the development of migraine to a severe dysregulation of cerebral vascular tone. Furthermore, the critical role of the serotonergic system in the formation of this pathology has been reliably confirmed.

Classification of drugs for acute attack relief

The migraine pharmacotherapy strategy is clearly divided into acute attack management and future attack prophylaxis. In modern medicine, two main groups of drugs are used for emergency pain relief.

The first group is non-specific analgesics. They are used as general pain-relieving agents. This category includes:

• Non-opioid analgesics (paracetamol being the basic representative).
• Non-steroidal anti-inflammatory drugs, or NSAIDs (acetylsalicylic acid and ibuprofen are most commonly used).

The second group consists of specific agents that directly affect cerebral circulation. Their mechanism of action is based on the stimulation of serotonin receptors (especially the 5-HT1D subtype). These include:

• Serotonin receptor agonists (triptans). The main drug of this group is sumatriptan. Its pathogenetic mechanism for pain relief lies in reducing the excessive pulsation of cerebral vessels, which is the root cause of the headache during a migraine attack.
• Ergot alkaloids. These include ergotamine and its hydrogenated derivatives. An important feature is the dosage form: for example, dihydroergotamine is actively used as a nasal spray, ensuring convenience during an attack.

Symptomatic therapy and prophylaxis in the interictal period

Attack relief is not limited to combating pain alone. To eliminate associated dyspeptic disorders, particularly vomiting, antiemetics are used. The primary drug of choice in this situation is metoclopramide.

If attacks occur frequently, prophylactic therapy is prescribed to the patient. It is administered strictly during the interictal period. The main goal of such treatment is a significant reduction in the frequency and severity of future attacks. Drugs from completely different pharmacological groups are used for prophylaxis:

• Serotonin receptor antagonists (block 5-HT2 receptors): methysergide.
• Beta-blockers: propranolol.
• Tricyclic antidepressants: amitriptyline.
• Antiepileptic drugs (anticonvulsants): carbamazepine and clonazepam.

Class and exam questions

What else to study on this topic

• The role of the serotonergic system in the pathogenesis of migraine
• Mechanism of action of 5-HT1D receptor agonists on cerebral blood vessels
• Pharmacodynamics and dosage forms of ergot alkaloids
• Principles of drug selection for prophylactic therapy in the interictal period

Other topics in the section "Drugs used for cerebral circulatory disorders"

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