27.1 Primary Acute Headaches: Migraine, Tension & Cluster

ABFM Family Medicine Certification Study Guide Exam

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1 Chapter 1: Exam Structure, Blueprint & Clinical Decision-Making

1.1 Exam Blueprint, FMCLA vs. One-Day Exam & Board Scoring 1.2 Clinical Reasoning, Test-Taking Strategy & Ambiguity Management 1.3 Evidence-Based Medicine & Clinical Practice Guidelines in Primary Care

2 Chapter 2: Healthcare Systems, Practice Management & Quality

2.1 Practice Management, Billing, Coding & Documentation 2.2 Quality Improvement, Patient Safety & Diagnostic Stewardship 2.3 Interprofessional Team-Based Care & Care Coordination

3 Chapter 3: Ethics, Law, Biostatistics & Health Equity

3.1 Medical Ethics, Informed Consent & Surrogate Decision-Making 3.2 Biostatistics, Clinical Epidemiology & Diagnostic Test Interpretation 3.3 Social Determinants of Health, Health Equity & Cultural Humility 3.4 Physician Wellness, Burnout Prevention & Professionalism

4 Chapter 4: Lifestyle Counseling & Behavior Change

4.1 Alcohol Use Screening & Brief Intervention 4.2 Illicit Drug & Cannabis Counseling 4.3 Tobacco & Vaping Cessation Counseling

5 Chapter 5: Nutrition, Physical Activity & Chronic Disease Prevention

5.1 Dietary Counseling for Obesity & Chronic Disease Prevention 5.2 Exercise Prescription & Physical Activity Counseling 5.3 Genetic Risk Assessment & Family History Counseling

6 Chapter 6: Routine Adult Immunizations

6.1 ACIP Adult Respiratory Vaccines: Influenza, COVID-19, RSV & Pneumococcal 6.2 ACIP Adult Non-Respiratory Vaccines: Tdap, Shingrix, HPV & Hep B 6.3 Immunizations in Special Populations: Pregnancy, Asplenia & Immunocompromise

7 Chapter 7: Pediatric Health Maintenance & Surveillance

7.1 Newborn Examination & Early Postnatal Care 7.2 Well-Child Care, Developmental Surveillance & Milestones 7.3 Pediatric & Adolescent Screening: Vision, Hearing, Anemia & Lead 7.4 Pediatric Oral Health, Dental Screening & Fluoride

8 Chapter 8: Behavioral Health & Safety Screening

8.1 Primary Care Depression, Anxiety & Behavioral Health Screening 8.2 Domestic Violence, Intimate Partner Violence & Firearm Safety 8.3 Occupational Health & Recreational Safety Counseling

9 Chapter 9: Adult Preventive Screening: Cardiovascular & Metabolic

9.1 Cardiovascular Disease & Hypertension Screening 9.2 Type 2 Diabetes Screening & Prediabetes Risk Stratification 9.3 Abdominal Aortic Aneurysm & Osteoporosis Screening

10 Chapter 10: Adult Cancer Screening: Breast & Gynecologic

10.1 Breast Cancer Screening & Risk-Assessment 10.2 Cervical Cancer Screening & ASCCP Algorithms 10.3 Skin Cancer Clinical Assessment & Counseling

11 Chapter 11: Adult Cancer Screening: Colorectal, Lung & Prostate

11.1 Colorectal Cancer Screening Modalities & Intervals 11.2 Lung Cancer Screening with Low-Dose CT 11.3 Prostate Cancer Screening & Shared Decision-Making

12 Chapter 12: Sexual Health, Infectious Disease Screening & Contraception

12.1 Sexual Health Counseling & Risk-Reduction Strategies 12.2 STI Screening: Chlamydia, Gonorrhea, Syphilis & Trichomoniasis 12.3 Bloodborne Infectious Disease Screening: HIV & Hepatitis C

13 Chapter 13: Reproductive Life Planning, Lactation & Preoperative Care

13.1 Preconception Planning & Comprehensive Contraception Management 13.2 Lactation Support & Breastfeeding Counseling 13.3 Preoperative Medical Evaluation & Pre-Participation Sports Exam

14 Chapter 14: Emergent Cardiovascular Conditions

14.1 Acute Coronary Syndromes & Myocardial Infarction 14.2 Acute Chest Pain Risk Stratification & Triage 14.3 Acute or Critical Valvular Heart Emergencies

15 Chapter 15: Cardiac Arrhythmias, Heart Failure & Hypertensive Crises

15.1 Acute Atrial & Ventricular Arrhythmias 15.2 Acute Decompensated Heart Failure & Cardiogenic Shock 15.3 Hypertensive Emergency & Urgency Management

16 Chapter 16: Vascular & Thromboembolic Emergencies

16.1 Pulmonary Embolism & Deep Vein Thrombosis 16.2 Acute Aortic Syndromes & Peripheral Vascular Emergencies 16.3 Critical Limb Ischemia & Acute Arterial Occlusion

17 Chapter 17: Neurologic Emergencies: Stroke & Altered Consciousness

17.1 Acute Ischemic Stroke & Intracranial Hemorrhage 17.2 Syncope Evaluation & Status Epilepticus 17.3 Acute Delirium, Encephalopathy & Severe Confusion

18 Chapter 18: Neurologic Trauma & Acute Cranial Emergencies

18.1 Concussion, Moderate-to-Severe TBI & Intracranial Injury 18.2 Thunderclap & Acute Severe Secondary Headaches 18.3 Acute Ophthalmologic Emergencies

19 Chapter 19: Acute Abdominal, Pelvic & Gastrointestinal Emergencies

19.1 Acute Abdominal & Pelvic Pain Triage 19.2 Upper & Lower Gastrointestinal Bleeding 19.3 Acute Hepatic Failure, Cholangitis & Severe Jaundice

20 Chapter 20: Acute Pulmonary & Airway Emergencies

20.1 Acute Hypoxic Respiratory Failure & ARDS 20.2 Severe Community-Acquired Pneumonia & Empyema 20.3 Acute Severe Epistaxis & Airway Obstruction

21 Chapter 21: Acute Traumatic Injuries & Wound Care

21.1 Major Trauma Resuscitation & Initial Assessment 21.2 Burn Assessment, Inhalation Injury & Resuscitation 21.3 Laceration Management, Complex Wounds & Animal Bites

22 Chapter 22: Acute Orthopedic & Musculoskeletal Emergencies

22.1 Acute Ambulatory Fractures & Initial Splinting 22.2 Compartment Syndrome & Major Orthopedic Trauma 22.3 Septic Arthritis & Acute Microcrystalline Crises

23 Chapter 23: Severe Infections, Sepsis & Systemic Emergencies

23.1 Sepsis, Septic Shock & Initial Fluid Resuscitation 23.2 Necrotizing Soft Tissue Infections & Severe CNS Infections 23.3 Anaphylaxis Diagnosis, Epinephrine Dosing & Airway Protection

24 Chapter 24: Metabolic, Endocrine & Electrolyte Emergencies

24.1 Diabetic Ketoacidosis & Hyperosmolar Hyperglycemic State 24.2 Critical Electrolyte Emergencies: Dyskalemias & Dysnatremias 24.3 Severe Calcium Abnormalities & Acute Adrenal Crisis

25 Chapter 25: Hematologic, Urologic & Dental Emergencies

25.1 Severe Symptomatic Anemias & Coagulopathic Emergencies 25.2 Testicular Torsion, Priapism & Acute Urinary Retention 25.3 Urgent Odontogenic Infections & Dental Trauma

26 Chapter 26: Psychiatric, Behavioral & Obstetric/Gynecologic Emergencies

26.1 Suicidal Ideation, Acute Agitation & Behavioral Emergencies 26.2 Acute Physical & Sexual Assault Care 26.3 Life-Threatening Vaginal Bleeding & Ectopic Pregnancy 26.4 Environmental Heat Stroke & Severe Hypothermia

27 Chapter 27: Acute Head, Neck & Neurologic Symptoms

27.1 Primary Acute Headaches: Migraine, Tension & Cluster 27.2 Concussion & Minor Closed Head Injury Evaluation 27.3 Transient Ischemic Attack Evaluation & ABCD2 Risk Scoring

28 Chapter 28: Acute Cranial Nerves, Hearing & Sensory Symptoms

28.1 Peripheral Neuropathies: Bell's Palsy, Carpal Tunnel & Radiculopathy 28.2 Acute Tinnitus, Sudden Sensorineural Hearing Loss & Cerumen Impaction 28.3 Acute Dizziness, Benign Paroxysmal Positional Vertigo & Vestibular Neuritis

29 Chapter 29: Acute Upper Respiratory Tract Infections

29.1 Acute Viral Rhinosinusitis vs. Bacterial Rhinosinusitis 29.2 Acute Pharyngitis: Group A Streptococcus & Centor Criteria 29.3 Acute Otitis Media, Otitis Externa & Serous Effusion

30 Chapter 30: Acute Lower Respiratory Infections & Cough

30.1 Influenza, COVID-19 & Viral Respiratory Syndromes 30.2 Acute Bronchitis & Lower Respiratory Tract Infections 30.3 Ambulatory Community-Acquired Pneumonia

31 Chapter 31: Allergic, Nasal & Non-Infectious Pulmonary Conditions

31.1 Allergic Rhinitis & Acute Non-Anaphylactic Allergic Reactions 31.2 Acute Dyspnea in Ambulatory Care 31.3 Interstitial Lung Diseases & Sarcoidosis Presentation

32 Chapter 32: Acute Chest, Cardiac & Vascular Symptoms

32.1 Palpitations Evaluation & Arrhythmia Triage in Primary Care 32.2 Deep Vein Thrombosis & Superficial Thrombophlebitis 32.3 Ambulatory Hypotension & Orthostasis Evaluation

33 Chapter 33: Acute Upper Gastrointestinal Conditions

33.1 Peptic Ulcer Disease & Gastritis 33.2 Dysphagia, Esophagitis & Acute Esophageal Disorders 33.3 Acute Nausea, Vomiting & Foodborne Illness

34 Chapter 34: Acute Lower Gastrointestinal Conditions

34.1 Acute Infectious Diarrhea & Gastroenteritis 34.2 Acute Constipation & Functional Bowel Changes 34.3 Ano-Rectal Disorders: Hemorrhoids, Fissures, Abscesses & Pruritus Ani

35 Chapter 35: Inflammatory, Functional & Malabsorptive GI Disorders

35.1 Acute Flares of Inflammatory Bowel Disease 35.2 Irritable Bowel Syndrome: Diagnosis, Subtyping & Management 35.3 Celiac Disease & Malabsorption Syndromes

36 Chapter 36: Acute Abdominal, Hepatic & Biliary Disorders

36.1 Ambulatory Abdominal & Pelvic Pain Triage 36.2 Acute Cholecystitis, Biliary Colic & Pancreatitis 36.3 Acute Liver Injury & Viral Hepatitis

37 Chapter 37: Acute Abdominal Wall, Hernias & Dental Conditions

37.1 Abdominal Wall, Inguinal & Ventral Hernias 37.2 Acute Dental Pain, Odontogenic Abscess & Aphthous Ulcers 37.3 Acute Edema: Unilateral vs. Bilateral Diagnostic Evaluation

38 Chapter 38: Acute Infectious Dermatoses

38.1 Bacterial Skin Infections: Impetigo, Cellulitis & Cutaneous Abscesses 38.2 Fungal Skin Infections: Tinea Corporis, Cruris, Pedis & Onychomycosis 38.3 Viral Cutaneous Infections: Herpes Simplex, Zoster & Molluscum Contagiosum

39 Chapter 39: Inflammatory, Allergic & Autoimmune Dermatoses

39.1 Atopic Dermatitis, Contact Dermatitis & Eczematous Flares 39.2 Non-Infectious Rashes: Urticaria, Drug Eruptions & Erythema Multiforme 39.3 Cutaneous Malignancies & Premalignant Lesions: AK, BCC, SCC & Melanoma

40 Chapter 40: Acute Shoulder, Elbow & Upper Extremity Injuries

40.1 Rotator Cuff Pathology, Tendinopathy & Shoulder Impingement 40.2 Lateral & Medial Epicondylitis, Olecranon Bursitis & Elbow Sprains 40.3 Wrist & Hand Soft-Tissue Injuries: De Quervain, TFCC & Finger Sprains

41 Chapter 41: Acute Knee, Ankle & Lower Extremity Injuries

41.1 Meniscal Tears, Ligamentous Knee Injuries & Patellofemoral Pain 41.2 Ankle Sprains, Ottawa Ankle Rules & Achilles Tendinopathy 41.3 Plantar Fasciitis, Shin Splints & Overuse Syndromes

42 Chapter 42: Acute Ambulatory Fractures & Dislocations

42.1 Distal Radius, Scaphoid & Common Upper Extremity Fractures 42.2 Metatarsal, Clavicle & Common Lower Extremity Fractures 42.3 Joint Dislocation Management: Nursemaid's Elbow & Shoulder Subluxation

43 Chapter 43: Acute Axial Musculoskeletal Pain & Falls

43.1 Acute Low Back Pain: Red Flags, Strain & Disc Herniation 43.2 Acute Cervical Strain, Whiplash & Axial Neck Pain 43.3 Evaluation of Falls in Ambulatory & Older Patients

44 Chapter 44: Acute Inflammatory Arthropathies & Generalized Pain

44.1 Acute Inflammatory Arthritis & Spondyloarthropathies 44.2 Myalgias, Rhabdomyolysis & Post-Viral Pain Syndromes 44.3 Acute Non-Headache Pain Management Strategies

45 Chapter 45: Acute Renal, Urinary & Genitourinary Conditions

45.1 Uncomplicated UTI, Pyelonephritis & Acute Urethritis 45.2 Hematuria Workup & Glomerulonephritis 45.3 Nephrolithiasis & Acute Urinary Tract Obstruction

46 Chapter 46: Acute Male Genitourinary & Prostatic Conditions

46.1 Acute Prostatitis, Epididymitis & Orchitis 46.2 Acute Scrotal Pain: Torsion vs Appendage, BPH & Male Genital Emergencies 46.3 Acute Urinary Retention & Incontinence Evaluation

47 Chapter 47: Acute Women's Health & Early Pregnancy Care

47.1 Early Pregnancy Diagnosis, Dating & Initial Complications 47.2 Abnormal Uterine Bleeding & Acute Menstrual Disorders 47.3 Premenstrual Syndrome & Premenstrual Dysphoric Disorder

48 Chapter 48: Breast Disorders, STIs & Pediatric Elimination

48.1 Palpable Breast Mass, Mastitis & Nipple Discharge 48.2 Sexually Transmitted Infections: Diagnosis, Staging & CDC Guidelines 48.3 Pediatric Enuresis & Encopresis

49 Chapter 49: Systemic Signs, Metabolic Dysregulation & Miscellaneous Infections

49.1 Acute Fever, Sepsis Screening & FUO in Primary Care 49.2 Acute Hyperglycemia & Symptomatic Hypoglycemia 49.3 Electrolyte Abnormalities: Mild-to-Moderate Disturbances 49.4 Vector-Borne, Tick-Borne & Rickettsial Illnesses

50 Chapter 50: Chronic Cardiovascular Diseases: Hypertension & Ischemia

50.1 Essential Hypertension Management: 2025 AHA/ACC Guideline & JNC Strategies 50.2 Chronic Coronary Artery Disease & Post-MI Secondary Prevention 50.3 Chronic Heart Failure: HFrEF, HFpEF & Quadruple GDMT

51 Chapter 51: Chronic Vascular, Valvular & Dyslipidemic Diseases

51.1 Peripheral Arterial Disease & Claudication 51.2 Chronic Valvular Heart Disease & Murmur Evaluation 51.3 Lipid Disorders & ASCVD Risk-Based Statin Therapy

52 Chapter 52: Chronic Respiratory Diseases: Asthma & COPD

52.1 Chronic Asthma Management: GINA Stepwise SMART Therapy 52.2 Chronic Obstructive Pulmonary Disease: GOLD Recommendations 52.3 Solitary Pulmonary Nodule Evaluation & Fleischner Society Criteria

53 Chapter 53: Chronic Metabolic Diseases: Diabetes Mellitus

53.1 Type 2 Diabetes Management: ADA Pharmacotherapy Algorithms 53.2 Type 1 Diabetes: Basal-Bolus Insulin, CGMs & Diabetic Complications 53.3 Diabetic Microvascular & Macrovascular Disease Surveillance

54 Chapter 54: Obesity, Nutrition & Metabolic Bone Diseases

54.1 Medical & Behavioral Management of Obesity & Incretin Mimetics 54.2 Osteoporosis & Metabolic Bone Disease: DEXA, FRAX & Antiresorptives 54.3 Nutritional Deficiencies: Vitamin D, B12, Iron & Malnutrition

55 Chapter 55: Chronic Endocrine Disorders

55.1 Primary & Subclinical Hypothyroidism, Hyperthyroidism & Nodules 55.2 Adrenal Disorders: Addison's Disease & Cushing's Syndrome 55.3 Hypercalcemia, Hyperparathyroidism & Pituitary Disorders

56 Chapter 56: Chronic Kidney Disease & Venous Disorders

56.1 Chronic Kidney Disease: KDIGO Staging & Renoprotective Therapy 56.2 Chronic Venous Insufficiency, Stasis Dermatitis & Lymphedema 56.3 Chronic Electrolyte & Acid-Base Management in CKD

57 Chapter 57: Chronic Gastrointestinal & Hepatic Diseases

57.1 Gastroesophageal Reflux Disease, Barrett's Esophagus & Dyspepsia 57.2 Chronic Liver Disease: MASLD/NAFLD, Cirrhosis & Portal Hypertension 57.3 Viral Hepatitis B & C: Long-Term Monitoring & DAA Therapy

58 Chapter 58: Colorectal Surveillance & Chronic Pancreaticobiliary Care

58.1 Post-Polypectomy Colorectal Polyp Surveillance Guidelines 58.2 Chronic Pancreatitis & Exocrine Pancreatic Insufficiency 58.3 Chronic Nausea, Gastroparesis & Functional GI Disorders

59 Chapter 59: Chronic Musculoskeletal & Rheumatologic Disorders

59.1 Osteoarthritis: Hip, Knee & Hand Management 59.2 Spinal Conditions: Spinal Stenosis, Spondylolisthesis & Compression Fractures 59.3 Chronic Myopathies & Fibromyalgia Syndrome

60 Chapter 60: Chronic Neurologic & Neurodegenerative Disorders

60.1 Dementia: Alzheimer's, Vascular & Lewy Body Disease 60.2 Parkinson's Disease & Essential Tremor 60.3 Epilepsy: Chronic Antiseizure Medications & Post-Stroke Care

61 Chapter 61: Chronic Peripheral Nerves, Pain & Sensory Disorders

61.1 Diabetic & Chronic Peripheral Neuropathies 61.2 Chronic Pain Syndromes & Chronic Daily Headaches 61.3 Chronic Tinnitus, Presbycusis & Persistent Dizziness

62 Chapter 62: Chronic Psychiatric Disorders

62.1 Major Depressive Disorder & Generalized Anxiety Disorder 62.2 Bipolar Disorder: Maintenance Pharmacotherapy & Lithium Monitoring 62.3 Adult & Pediatric Attention-Deficit/Hyperactivity Disorder

63 Chapter 63: Chronic Behavioral Health & Neurodevelopmental Conditions

63.1 Chronic Behavioral Conditions: PTSD, OCD & Somatization 63.2 Autism Spectrum Disorder & Intellectual Disabilities 63.3 Eating Disorders: Anorexia Nervosa, Bulimia & Binge Eating

64 Chapter 64: Chronic Substance Use Disorders & Tobacco Cessation

64.1 Alcohol Use Disorder: Pharmacotherapy & Relapse Prevention 64.2 Opioid & Stimulant Use Disorders: MOUD & Harm Reduction 64.3 Longitudinal Tobacco Cessation Pharmacotherapy

65 Chapter 65: Chronic Dermatologic Conditions

65.1 Acne Vulgaris, Rosacea & Seborrheic Dermatitis 65.2 Chronic Plaque Psoriasis & Biologic Therapies 65.3 Chronic Eczema, Hidradenitis Suppurativa & Cutaneous Lupus

66 Chapter 66: Chronic Reproductive, Infectious & Geriatric Special Care

66.1 Chronic Menstrual Disorders, Infertility & Sexual Dysfunction 66.2 Menopause Management & Hormone Replacement Therapy 66.3 Chronic HIV Infection Management & Primary Care Integration 66.4 Gender-Affirming Primary Care & Hormone Therapy 66.5 Advance Care Planning, Palliative Care & End-of-Life Symptom Control

67 Chapter 67: Continuity Care: Sleep, Fatigue, Cancer, Pregnancy & the Adult Preventive Visit

67.1 Chronic Insomnia & Obstructive Sleep Apnea 67.2 Chronic Malaise, Fatigue & ME/CFS 67.3 Primary Care During Cancer Treatment & Survivorship 67.4 Routine Prenatal Care & Longitudinal Pregnancy Management 67.5 The Periodic Adult Health Examination & Medicare Annual Wellness Visit

27.1 Primary Acute Headaches: Migraine, Tension & Cluster

Key Takeaways Explain This Topic AI

The POUND mnemonic (Pulsatile, One-day [4-72h], Unilateral, Nausea/vomiting, Disabling) provides high diagnostic accuracy for migraine, with 4-5 features conferring a positive likelihood ratio (+LR) of 24.

Triptans (5-HT1B/1D agonists) are first-line abortive agents for moderate-to-severe migraine, but are strictly contraindicated in coronary artery disease, prior stroke/TIA, uncontrolled hypertension, peripheral vascular disease, hemiplegic/basilar migraine, and pregnancy; in these patients, CGRP antagonists (gepants) or ditans (lasmiditan, with an 8-hour driving ban) are safe alternatives.

Intravenous dopamine antagonists (metoclopramide 10 mg, prochlorperazine 10 mg) offer potent synergistic abortive analgesia and antiemetic efficacy in urgent settings, but must be co-administered with diphenhydramine (25-50 mg) to prevent akathisia and acute dystonic reactions.

Medication Overuse Headache (MOH) is diagnosed when headache occurs on ≥15 days/month for >3 months in patients using triptans, ergots, opioids, or combination analgesics (butalbital) on ≥10 days/month, or simple NSAIDs/acetaminophen on ≥15 days/month; opioids and butalbital must be avoided due to high rebound and dependence liability.

Cluster headache presents as excruciating unilateral periorbital/temporal stabbing pain lasting 15-180 minutes with ipsilateral autonomic features (lacrimation, rhinorrhea, Horner syndrome); acute first-line treatment is 100% High-Flow Oxygen (12-15 L/min via non-rebreather mask for 15 minutes, >75% efficacy) and subcutaneous sumatriptan 6 mg, while verapamil is first-line prophylaxis requiring serial ECG monitoring for PR prolongation.

Last updated: September 2026

Primary Acute Headaches: Clinical Spectrum & Secondary Headache Red Flags

Headaches represent one of the most common chief complaints in ambulatory family medicine, accounting for millions of clinic visits annually. The primary care physician's first objective is to differentiate benign primary headache disorders—primarily migraine , tension-type headache (TTH) , and cluster headache / trigeminal autonomic cephalgias —from life-threatening secondary headaches requiring emergent neuroimaging, lumbar puncture, or surgical intervention.

The SNOOP4 Secondary Headache Red Flag Criteria

The presence of any "red flag" symptom demands immediate escalation, emergent non-contrast head CT, or emergency department transfer to rule out conditions such as aneurysmal subarachnoid hemorrhage, bacterial meningitis, intracranial mass lesion, acute angle-closure glaucoma, or temporal (giant cell) arteritis. THE SNOOP4 RED FLAG SYSTEM

• S - Systemic symptoms: Fever, night sweats, unexplained weight loss,
• immunocompromised status (HIV, active chemotherapy), or history of cancer
• N - Neurologic signs/symptoms: Focal motor or sensory deficits, papilledema,
• altered mental status, cognitive decline, seizures, or neck stiffness
• O - Onset sudden / "Thunderclap": Pain reaching peak excruciating intensity
• in < 1 minute (hallmark of subarachnoid hemorrhage, RCVS, or CVST)
• O - Older age at onset: New or progressive headache beginning at age ≥ 50 years
• (high suspicion for Giant Cell Arteritis or intracranial neoplasm)
• P1 - Pattern change or Progressive: Escalating frequency, change in attack
• morphology, or "worst headache of life"
• P2 - Positional triggers: Pain substantially worsening upon standing upright
• (low CSF pressure / leak) or lying flat (elevated ICP / mass / IIH)
• P3 - Precipitated by Valsalva: Headache provoked by coughing, sneezing, bending,
• or strenuous exertion (raises concern for posterior fossa lesion/Chiari)
• P4 - Papilledema: Optic disc swelling on fundoscopy indicating elevated ICP
• Migraine Headache: Pathophysiology, Clinical Features & Diagnostic Criteria

Migraine is a chronic, neurovascular pain disorder characterized by recurrent episodic attacks of moderate-to-severe headache accompanied by neurological, autonomic, and gastrointestinal symptoms.

Neurobiology & Pathophysiology

Trigeminovascular System Activation : The core generator of migraine pain involves activation of pseudo-unipolar primary sensory neurons located within the trigeminal ganglion. These neurons innervate the pain-sensitive intracranial meninges and dural blood vessels.

Neurogenic Inflammation : Antidromic stimulation of these sensory fibers leads to the local release of potent vasoactive neuropeptides, most notably Calcitonin Gene-Related Peptide (CGRP) , substance P, and neurokinin A. CGRP binds to receptors on dural mast cells and vascular smooth muscle, causing mast cell degranulation, sterile neurogenic plasma extravasation, marked vasodilation, and sustained nociceptive sensitization of trigeminal caudate neurons in the brainstem.

Cortical Spreading Depression (CSD) : The neurobiological substrate of the migraine aura . CSD is a slowly propagating wave (2 to 6 mm/minute) of intense neuronal and glial depolarization across the cerebral cortex, primarily originating in the occipital visual cortex. This depolarizing wave is accompanied by transient hyperperfusion followed by prolonged oligemia (reduced cortical blood flow) and prolonged neuronal suppression, activating meningeal nociceptors and opening the blood-brain barrier.

Clinical Diagnostic Criteria (ICHD-3) & The POUND Mnemonic

According to the International Classification of Headache Disorders (ICHD-3), a diagnosis of migraine without aura requires at least 5 attacks meeting the following parameters:

Attack duration lasting 4 to 72 hours (untreated or unsuccessfully treated);

At least two of the following four pain characteristics:

• Unilateral location;
• Pulsating / throbbing quality;
• Moderate to severe pain intensity (inhibits or prohibits daily activities);
• Aggravation by or causing avoidance of routine physical activity (e.g., walking, climbing stairs);

At least one of the following associated symptoms during the attack:

Nausea and/or vomiting;

Both photophobia (light sensitivity) and phonophobia (sound sensitivity).

To rapidly identify migraine in the clinic, the validated POUND mnemonic is widely utilized:

• P - P ulsatile / throbbing quality
• O - O ne-day duration (typically 4 to 72 hours)
• U - U nilateral location
• N - N ausea or vomiting
• D - D isabling intensity (disrupts daily activities)

Diagnostic Accuracy : The presence of 4 or 5 POUND features provides a positive likelihood ratio (+LR) of 24 , virtually confirming migraine. The presence of 3 features yields a +LR of 3.2, whereas ≤2 features has a -LR of 0.41, arguing against migraine.

Migraine with Aura vs. Without Aura

Approximately 25% to 30% of patients experience migraine with aura.

Aura Characteristics : Neurological symptoms that are completely reversible, develop gradually over ≥5 minutes , and typically last 5 to 60 minutes (rarely up to 4 hours), immediately preceding or accompanying the headache phase.

Aura Modalities :

Visual Aura (>90% of auras): The classic scintillating scotoma (a luminous, flickering, jagged zigzag pattern resembling a fortified city wall [ fortification spectrum or teichopsia ]) that gradually expands across the visual field, leaving a central or paracentral blind spot (scotoma).

Sensory Aura : Unilateral paresthesias ("pins and needles") typically marching slowly from the fingers up the arm to the face and tongue, followed by numbness.

Speech / Language Aura : Transient expressive dysphasia, paraphasias, or word-finding difficulties.

Differentiating Aura from Transient Ischemic Attack (TIA) : A critical clinical distinction. Migraine aura characteristically displays a gradual evolutionary "march" over 5 to 20 minutes characterized by "positive" phenomena (flashing lights, shimmering lines, tingling paresthesias). In contrast, a TIA produces an abrupt, sudden-onset deficit reaching maximal intensity in seconds characterized by "negative" loss-of-function phenomena (sudden blindness, complete loss of sensation, dense motor paralysis).

Stepwise Acute Abortive Pharmacotherapy for Migraine

Modern migraine management uses a stratified care approach : matching the initial treatment to attack severity and disability rather than utilizing a rigid step-up approach that forces severely disabled patients through ineffective low-tier medications. STRATIFIED ACUTE MIGRAINE PHARMACOTHERAPY

• MILD TO MODERATE ATTACKS
• ┌─────────────────────────────────────────────────────────────┐
• │ • Oral NSAIDs: Ibuprofen 400-800 mg, Naproxen 500-550 mg │
• │ • Acetaminophen 1,000 mg (alone or with Caffeine/Aspirin) │
• │ • Limit use to <15 days/month to avoid medication overuse │
• └──────────────────────────────┬──────────────────────────────┘
• ▼
• MODERATE TO SEVERE ATTACKS
• ┌─────────────────────────────────────────────────────────────┐
• │ 1. FIRST-LINE: Triptans (5-HT1B/1D Agonists) │
• │ • Sumatriptan (50-100 mg PO, 6 mg SC, 20 mg Nasal) │
• │ • Zolmitriptan, Rizatriptan (cap 5 mg if on propranolol) │
• │ • CONTRAINDICATED in CAD, stroke/TIA, uncontrolled HTN │
• ├─────────────────────────────────────────────────────────────┤
• │ 2. VASCULAR CONTRAINDICATIONS OR TRIPTAN NON-RESPONDERS: │
• │ • CGRP Antagonists (Gepants): Rimegepant, Ubrogepant │
• │ *No vasoconstriction; safe in cardiovascular disease* │
• │ • 5-HT1F Agonist (Ditan): Lasmiditan 50-100 mg │
• │ *No vasoconstriction; mandatory 8-hour driving ban* │
• ├─────────────────────────────────────────────────────────────┤
• │ 3. EMERGENCY / URGENT CARE RESCUE: │
• │ • IV Metoclopramide 10 mg OR Prochlorperazine 10 mg │
• │ PLUS Diphenhydramine 25-50 mg (prevents akathisia) │
• │ • IV Ketorolac 30 mg + IV Dexamethasone 10 mg (prevents │
• │ headache recurrence over next 72 hours) │
• └─────────────────────────────────────────────────────────────┘
• 1. Triptans (5-HT1B / 5-HT1D Receptor Agonists)

Mechanism of Action :

Selective agonists at 5-HT1B receptors located on cranial and meningeal vascular smooth muscle, causing selective cranial vasoconstriction;

Selective agonists at presynaptic 5-HT1D receptors on trigeminal sensory nerve terminals, inhibiting the release of pro-inflammatory neuropeptides (CGRP, substance P);

Central inhibition of second-order nociceptive transmission within the trigeminal nucleus caudalis.

Formulations & Routes :

Sumatriptan : 50-100 mg PO; 6 mg Subcutaneous (onset within 10-15 minutes; gold standard for rapid rescue or severe early vomiting); 5-20 mg nasal spray;

Zolmitriptan : 2.5-5 mg PO/ODT; 5 mg nasal spray;

Rizatriptan : 5-10 mg PO/ODT (fastest oral onset; Clinical Pearl : If co-administered with propranolol, the dose of rizatriptan must be capped at 5 mg because propranolol inhibits rizatriptan metabolism, increasing serum concentrations by 70%);

Eletriptan : 20-40 mg PO (highest bioavailability and receptor affinity).

STRICT CONTRAINDICATIONS (HIGH-YIELD BOARD PEARL) :

Because 5-HT1B activation produces coronary and peripheral arterial vasoconstriction, triptans are strictly contraindicated in:

Ischemic Heart Disease : Coronary artery disease, history of myocardial infarction, coronary artery bypass grafting, or coronary stent placement;

• Coronary Vasospasm : Prinzmetal (variant) angina;
• Cerebrovascular Disease : Prior ischemic stroke or transient ischemic attack (TIA);
• Uncontrolled Hypertension : Blood pressure ≥140/90 mmHg or history of labile malignant hypertension;
• Peripheral Vascular Disease (PVD) or ischemic bowel disease;

Hemiplegic Migraine or Migraine with Brainstem Aura (basilar-type migraine), due to theoretical risk of ischemic stroke;

• Severe Hepatic Impairment ;
• Concurrent use of Ergotamines or another triptan within 24 hours;
• Concurrent use of MAO Inhibitors within 14 days (specifically for sumatriptan, rizatriptan, and zolmitriptan);

Pregnancy : Relative/strict contraindication due to potential uteroplacental vasoconstriction.

2. CGRP Receptor Antagonists (Gepants)

Agents : Rimegepant (75 mg ODT), Ubrogepant (50-100 mg PO), Zavegepant (10 mg nasal spray).

Mechanism : Small-molecule competitive antagonists that directly block the CGRP receptor on trigeminal neurons and meningeal vessels, interrupting neurogenic inflammation.

Critical Cardiovascular Safety Profile : Gepants DO NOT cause vasoconstriction of coronary, cerebral, or peripheral vascular beds. Consequently, gepants are the first-line choice for acute migraine abortive therapy in patients with coronary artery disease, history of stroke/TIA, uncontrolled hypertension, or peripheral vascular disease .

Dual Utility : Rimegepant is uniquely FDA-approved for both acute abortive therapy (75 mg PRN) and alternate-day preventive therapy (75 mg every other day).

3. Selective 5-HT1F Receptor Agonists (Ditans)

Agent : Lasmiditan (50 mg or 100 mg PO).

Mechanism : Highly selective agonist at the 5-HT1F receptor, inhibiting trigeminovascular nociceptive transmission without activating 5-HT1B receptors. Because it lacks 5-HT1B affinity, it produces zero vasoconstriction and can be used safely in patients with cardiovascular disease.

CNS Adverse Effects & Mandatory Driving Restriction : Lasmiditan crosses the blood-brain barrier readily, frequently causing dizziness, sedation, vertigo, and paresthesias. FDA Black Box Warning: Patients must NOT drive or operate heavy machinery for at least 8 hours following each dose.

4. Antiemetic Dopamine Antagonists & Emergency Cocktail

In the emergency department or urgent care setting, intravenous dopamine D2 receptor antagonists are highly effective abortive agents that also relieve nausea and overcome gastroparesis:

Metoclopramide 10 mg IV or Prochlorperazine 10 mg IV/IM .

Mandatory Co-Administration of Diphenhydramine : IV dopamine receptor blockade frequently provokes distressing extrapyramidal symptoms, particularly akathisia (severe motor restlessness and urge to pace) and acute dystonic reactions. Co-administering Diphenhydramine 25 to 50 mg IV/IM provides anticholinergic protection, preventing akathisia.

Preventing Migraine Recurrence : Adding Dexamethasone 10 mg IV does not immediately relieve pain but significantly reduces the rate of migraine recurrence over the subsequent 48 to 72 hours by ~30%.

5. Classes to AVOID in Acute Migraine

Opioids (codeine, oxycodone, hydromorphone) and Butalbital-containing combinations (Fioricet, Fiorinal) should be strictly avoided. They cause rapid tolerance, high rates of dependence, cognitive blunting, and are the most potent triggers for medication overuse headache and migraine chronification.

Medication Overuse Headache (MOH / Rebound Headache)

Medication Overuse Headache is a secondary headache disorder caused by the frequent, repetitive use of acute symptomatic headache medications in a patient with a pre-existing primary headache disorder.

• Diagnostic Criteria (ICHD-3)
• Headache occurring on ≥15 days per month in a patient with a pre-existing headache disorder;

Regular overuse of acute symptomatic headache medication for >3 months , defined as:

≥10 days per month for triptans, ergotamines, opioids, or combination analgesics (e.g., butalbital-acetaminophen-caffeine);

≥15 days per month for simple analgesics (acetaminophen, aspirin, NSAIDs) or any combination of simple analgesics.

Clinical Presentation & Vicious Cycle

Patients present with a chronic, daily or near-daily, dull-to-throbbing, holocephalic headache that is characteristically present upon awakening in the morning. When the patient consumes their overused medication, the headache temporarily subsides, only to rebound as the drug level falls hours later. This compels the patient to take another dose, establishing a self-sustaining vicious cycle.

Management Strategy for MOH

Patient Education : Explain the paradox that the medicine taken to relieve the headache has become the primary cause of daily pain.

Abrupt Discontinuation vs. Taper :

NSAIDs, acetaminophen, and triptans can be discontinued abruptly;

Butalbital combinations and opioids require a gradual outpatient taper to prevent severe withdrawal symptoms, rebound autonomic hyperactivity, or withdrawal seizures.

Transitional "Bridge" Therapy : During the 1- to 2-week withdrawal period, withdrawal headaches can be severe. Bridge options include:

• Oral Prednisone taper (e.g., 60 mg daily for 3 days, tapered by 20 mg every 3 days over 9-10 days);
• Scheduled long-acting NSAID (Naproxen sodium 500 mg BID for 10-14 days);

Greater Occipital Nerve (GON) blocks with 1% lidocaine and bupivacaine.

Early Initiation of Preventive Therapy : Start evidence-based preventive medications (Topiramate, Propranolol, Amitriptyline, or CGRP monoclonal antibodies [erenumab, fremanezumab, galcanezumab]) immediately upon initiating the withdrawal protocol.

Tension-Type Headache (TTH)

Tension-Type Headache is the most prevalent primary headache disorder, affecting over 40% of the population worldwide.

Clinical Characteristics & Diagnostic Criteria (ICHD-3)

Pain Quality : Non-pulsatile, dull, aching, band-like or vise-like tightness or pressure around the head, frequently involving the forehead, temples, and suboccipital neck muscles.

Location : Characteristically bilateral (diffuse or circumferential).

Intensity : Mild to moderate (does not completely disable the patient; patients can continue work or routine tasks).

Aggravation : NOT aggravated by routine physical activity (walking, climbing stairs).

Associated Symptoms : Absence of nausea and vomiting . Photophobia or phonophobia may be present, but never both simultaneously (if both are present, reclassify as migraine).

Classification : Infrequent episodic (<1 day/month), Frequent episodic (1 to 14 days/month), or Chronic (≥15 days/month for >3 months).

Treatment of Tension-Type Headache

Acute Abortive Therapy :

• Simple NSAIDs: Ibuprofen 400 to 800 mg PO, Naproxen sodium 500 mg PO;
• Acetaminophen 1,000 mg PO (preferred in pregnancy and renal impairment);

Combination analgesics: Acetaminophen + Aspirin + Caffeine.

Avoid : Triptans (ineffective in pure TTH), muscle relaxants (no proven superiority, high sedation), and opioids/butalbital (high MOH risk).

Prophylaxis (for Chronic or Frequent Episodic TTH) :

Indicated if headaches occur ≥2 days per week or significantly impair quality of life;

First-Line Prophylaxis : Amitriptyline (tricyclic antidepressant), initiated at 10 to 25 mg at bedtime and titrated up to 50 to 75 mg nightly. Mirtazapine or venlafaxine are second-line alternatives.

Cluster Headache: Trigeminal Autonomic Cephalgias (TACs)

Cluster headache is an excruciating, disabling primary headache disorder belonging to the family of Trigeminal Autonomic Cephalgias (TACs) . It is colloquially termed the "suicide headache" due to the agonizing intensity of individual attacks.

Epidemiology & Clinical Presentation

Demographics : Strong male predominance (male-to-female ratio ~3:1), with typical onset between ages 20 and 40 years. Heavily associated with a history of heavy cigarette smoking (>80% of patients).

Pain Profile :

Severity : Excruciating, boring, piercing, sharp, non-throbbing pain centered strictly unilaterally in the periorbital, retro-orbital, or temporal region (often described as "a hot poker being driven into the eye");

• Duration : Untreated attacks last 15 to 180 minutes ;
• Frequency : Attacks occur from once every other day up to 8 times per day ;

Episodic Clustering : Attacks cluster in episodic bouts lasting 6 to 12 weeks, separated by temporary remission periods lasting months to years. Chronobiological periodicity is striking: attacks recur at identical clockwork times each day, most commonly awakening the patient 1 to 2 hours after falling asleep (coinciding with REM sleep).

Ipsilateral Cranial Autonomic Features :

Driven by central trigeminal-parasympathetic reflex activation:

• Conjunctival injection (red eye) and lacrimation (tearing);
• Nasal congestion and/or rhinorrhea (runny nose);
• Eyelid edema;
• Forehead and facial diaphoresis (sweating);

Partial Horner Syndrome : Miosis (constricted pupil) and ptosis (drooping eyelid) on the side of the pain.

Behavioral Hallmark :

Unlike migraine patients who lie perfectly still in a dark, quiet room, cluster headache patients display profound motor restlessness and agitation , pacing the floor, rocking back and forth, banging their head, or crying out in agony.

Acute Abortive Treatment for Cluster Headache

Because cluster attacks peak within seconds to minutes and last <180 minutes, oral analgesics and oral triptans are completely ineffective due to slow gastrointestinal absorption.

100% High-Flow Oxygen (First-Line Gold Standard) :

Administration : Administer 100% oxygen at 12 to 15 L/minute via a non-rebreather face mask (with a well-sealed reservoir bag) for 15 minutes with the patient seated upright leaning forward;

Efficacy : Produces complete pain relief in >75% of patients within 15 minutes by inducing profound cerebral vasoconstriction and suppressing trigeminal sensory output;

Safety : Safe, highly effective, zero drug-drug interactions, and fully safe in patients with coronary artery disease or hypertension.

Subcutaneous Sumatriptan 6 mg :

The fastest and most effective pharmacologic abortive agent, achieving relief in 75% of attacks within 10 to 15 minutes (maximum dose: 12 mg in 24 hours, separated by at least 1 hour);

Alternative: Intranasal Zolmitriptan (5 to 10 mg nasal spray administered contralateral to the pain to bypass congested nasal mucosa).

Prophylactic Pharmacotherapy for Cluster Headache

Prophylaxis must be initiated immediately upon onset of a cluster period to suppress the cycle:

First-Line Maintenance Prophylaxis: Verapamil :

Calcium channel blocker; standard maintenance dose is 240 mg to 720 mg daily in divided doses;

MANDATORY ECG MONITORING (HIGH-YIELD BOARD PEARL) : Verapamil suppresses cardiac atrioventricular conduction. A baseline 12-lead ECG is mandatory , and follow-up ECGs must be obtained 10 to 14 days after every dose titration to screen for PR interval prolongation, second-degree or third-degree AV block, and severe bradycardia.

Transitional "Bridge" Therapy :

Because verapamil requires 1 to 2 weeks to reach therapeutic steady-state, bridge therapy is started simultaneously:

Oral Prednisone taper : 60 to 80 mg daily for 5 days, tapered down by 10-20 mg every 3 days over 2 to 3 weeks; OR

Suboccipital Corticosteroid Injection : Greater occipital nerve block with triamcinolone and bupivacaine, providing rapid temporary attack suppression.

CGRP Monoclonal Antibody: Galcanezumab :

Galcanezumab (300 mg subcutaneous loading dose administered as three 100 mg injections at cluster onset) is FDA-approved for episodic cluster headache, significantly reducing weekly attack frequency.

Summary Comparison of Primary Acute Headaches

• Feature Migraine Tension-Type Headache (TTH) Cluster Headache
• Sex Distribution Female > Male (3:1) Female ≥ Male (1.2:1) Male > Female (3:1)

Pain Location Unilateral (60-70%) or bilateral Bilateral (band-like / circumferential) Strictly Unilateral (periorbital / temporal)

Pain Quality Pulsating, throbbing Non-pulsatile, dull ache, pressure Piercing, boring, stabbing ("hot poker")

Pain Severity Moderate to severe (disabling) Mild to moderate (non-disabling) Excruciating, agonizing ("suicide pain")

Attack Duration 4 to 72 hours 30 minutes to 7 days 15 to 180 minutes

Aggravation by Activity Yes (prefers dark, quiet room) No (can continue daily activities) No; patient is severely restless / pacing

Associated Signs Nausea, vomiting, photophobia, phonophobia None; or only one of photophobia/phonophobia Ipsilateral autonomic (tearing, rhinorrhea, Horner)

First-Line Abortive Triptans, Gepants, NSAIDs NSAIDs, Acetaminophen 100% High-Flow O2 (12-15 L/min) , SC Sumatriptan

First-Line Prophylaxis Propranolol, Topiramate, Amitriptyline, CGRP mAbs Amitriptyline (10-75 mg PO QHS) Verapamil (240-720 mg/day) with serial ECGs

Loading diagram... Primary Acute Headache Triage & Clinical Algorithm