Chapter 30 Drugs for Headache Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. Headache Common symptom Triggered by a variety of stimuli Mild episodes Stress, fatigue, acute illness, sensitivity to alcohol Relieved by over-the-counter drugs (OTCs) (e.g., aspirin, acetaminophen) Severe headaches Migraine, cluster, tension-type Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 2 Medication Overuse Headache Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 3 Headaches Identifiable underlying causes Severe hypertension, hyperthyroidism, tumor, infection, and disorders of the eye, nose, sinuses, and throat No identifiable cause Migraine Cluster Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 4 Headaches Migraine headache I: characteristics and overview of treatment Migraine headache II: abortive therapy Migraine headache III: preventive therapy Cluster headaches Tension-type headache Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 5 Headaches Overview of treatment Drugs used in two ways Abort an ongoing attack • Aspirin-like drugs, opioid analgesics, migrainespecific drugs Prevent attacks from occurring • Beta blockers, TCAs, and antiepileptic drugs TCAs = tricyclic antidepressants. Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 6 Migraine Headache I Characteristics Throbbing head pain of moderate to severe intensity Nausea and vomiting Sensitivity to light and sound Highly debilitating Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 7 Migraine Headache I Characteristics (cont’d) Hormonal component Family history typical Two primary forms • Migraine with aura Preceded by visual symptoms More common than with aura • Migraine without aura Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 8 Migraine Headache I Pathophysiology Neurovascular disorder that involves dilation and inflammation of intracranial blood vessels Vasodilation leads to pain Neurons of the trigeminal vascular system Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 9 Migraine Headache I Overview of treatment Aborting an ongoing attack • Nonspecific analgesics Aspirin-like drugs and opioid analgesics Ergot alkaloids, serotonin1B/1D receptor agonists (triptans) • Migraine-specific drugs Preventing attacks from occurring • Beta blockers, TCAs, antiepileptic drugs Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 10 Migraine Headache I Nondrug measures Adequate sleep Exercise Avoiding triggers Once headache begins • Dark room with ice pack to neck Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 11 Migraine Headache II: Abortive Therapy Objective: to eliminate headache pain and suppress associated nausea/vomiting Earliest treatment possible Route of administration Oral not effective owing to GI distress Injection, inhalation, rectal suppository may be more effective Antiemetics Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 12 Selection of Drugs Mild to moderate headache Aspirin-like drugs • Aspirin, acetaminophen, ibuprofen, and other aspirin-like analgesics Moderate to severe Migraine-specific drug Opioid analgesics Antiemetics Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 13 Ergot Alkaloids Ergotamine Mechanism of antimigraine action • Exact mechanism unknown Therapeutic uses • Drug of choice to stop an ongoing migraine Pharmacokinetics • PO, sublingual, rectal, or inhalation Adverse effects • Nausea/vomiting, weakness in the legs, myalgia, numbness and tingling in fingers or toes, angina-like pain, tachycardia or bradycardia Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 14 Ergot Alkaloids Ergotamine (cont’d) Overdose • Ergotism Drug interactions • Triptans, CYP3A4 inhibitors Physical dependence • Risk of regular daily use Contraindications • Hepatic or renal impairment Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 15 Ergot Alkaloids Dihydroergotamine Therapeutic uses • Drug of choice for terminating migraine and cluster headaches Pharmacologic effects • Similar to ergotamine Pharmacokinetics • Only parenteral or nasal spray administration—not oral Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 16 Ergot Alkaloids Dihydroergotamine (cont’d) Drug interactions • CYP3A4 inhibitors, serotonin agonist Contraindications • Patients with coronary artery disease (CAD), peripheral vascular disease (PVD), sepsis, pregnancy, hepatic or renal impairment Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 17 Serotonin1B/1D Receptor Agonists Sumatriptan (Imitrex) Mechanism of action • Binds to receptors on intracranial blood vessels and causes vasoconstriction • Diminishes perivascular inflammation Therapeutic use • Aborting an ongoing migraine attack to relieve headache and associated symptoms Pharmacokinetics • Oral or intranasal administration Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 18 Serotonin1B/1D Receptor Agonists Sumatriptan (cont’d) Adverse effects • Chest symptoms Transient “heavy arms” or “chest pressure” experienced by 50% of users • Coronary vasospasm Rare angina secondary to vasospasm Vertigo, malaise, fatigue, tingling sensations Very bad taste when taken in intranasal form • Teratogenesis • Others Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 19 Serotonin1B/1D Receptor Agonists Drug interactions Ergot alkaloids, sumatriptan, other triptans (all cause vasoconstriction) Preparations, dosage, and administration Oral Nasal spray Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 20 Serotonin1B/1D Receptor Agonists Other serotonin1B/1D receptor agonists Zolmitriptan Naratriptan Rizatriptan Almotriptan Frovatriptan Eletriptan Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 21 Migraine Headache III Beta blockers Tricyclic antidepressants Antiepileptic drugs Preferred drugs for migraine prevention Divalproex Topiramate Estrogens (for menstrual migraine) Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 22 Migraine Headache III Other drugs for prophylaxis Calcium channel blockers Candesartan, an angiotensin II receptor blocker (ARB) Supplements • Riboflavin • Coenzyme Q-10 • Feverfew • Butterbur Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 23 Cluster Headaches Characteristics Occur in a series or “cluster” of attacks Each attack lasts 15 minutes to 2 hours Severe, throbbing, unilateral pain near the eye Lacrimation, conjunctival redness, nasal congestion, rhinorrhea, ptosis, miosis on the same side of the headache 1–2 attacks every day for 2–3 months An attack-free interval of months to years separates clusters Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 24 Cluster Headaches Treatment Primary therapy directed at prophylaxis Copyright © 2013, 2010 by Saunders, an imprint of Elsevier Inc. 25 Tension-Type Headache Characteristics Most common form of headache Moderate, nonthrobbing pain Usually located in a “head band” distribution May be episodic or chronic Treatment Nonopioid analgesics Patient teaching on how to manage stress Copyright © 2013, 2010 by Saunders, an imprint of 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