Numbers indicate IHS (International Headache Society) codes.

Classification of Headache
Mechanisms of Headaches
Transmission of Painful Impulses
Evaluation of the Patient with Headache

2.0: Tension-type headache
3.0: Cluster Headache and Chronic Paroxysmal Hemicrania
4.0: Miscellaneous headaches not associated with structural lesion
4.1: Idiopathic stabbing headache ("Icepick Headache")
4.2: External compression headache ("Swim Goggle Headache")
4.3: Cold stimulus headache ("Ice Cream Headache")
4.4: Benign cough headache
4.5: Benign exertional headache or effort migraine
4.6: Headache associated with sexual activity ("Coital or Orgasmic Headache")
5.0: Headache associated with trauma
5.1: Acute post-traumatic headache
5.2: Chronic post-traumatic headache
6.0: Headache associated with vascular disorders
            Referred Ophthalmic Division Pain and Occlusion of the Posterior Cerebral  Artery
            Ophthalmic Division Pain with Internal Carotid Artery Occlusion
6.1: Acute ischemic cerebrovascular disorder
6.2: Intracranial hematoma
6.3: Subarachnoid hemorrhage
          Sentinel headache

Thunderclap headaches

6.4: Unruptured vascular malformation
6.5: Arteritis
6.6: Carotid or vertebral artery pain
Arterial dissection
Carotidynia
6.7: Venous thrombosis
6.8: Arterial hypertension
6.9: Headache associated with other vascular disorder
           Postendarterectomy headache
7.0: Headache associated with nonvascular intracranial disorder
7.1: High CSF Pressure
7.2: Low CSF pressure
            Lumbar puncture headache
            Headache due to cerebrospinal fluid fistula
7.3: Intracranial infection
7.4: Intracranial sarcoidosis and other noninfectious inflammatory diseases
7.5: Headache related to intrathecal injections
7.6: Intracranial neoplasm (Brain tumor headache)
8.0: Headache associated with substances or their withdrawal
8.1: Headache induced by acute substance use or exposure
           Hot dog headache
          Chinese Restaurant Syndrome
           Vitamin-A-Induced Headache
8.2: Headache induced by chronic substance abuse or exposure
8.3: Headache from substance withdrawal (acute use)

"Hangover" headache

Post seizure headache

Headache associated with Infection or Fever

Headache Caused by Chemical Agents, with and without Anemic Cerebral Vasodilation

8.4: Headache from substance withdrawal (chronic use)
         Caffeine Withdrawal Headache (IHS category 8.4.2)
8.5: Headache associated with substance but with uncertain mechanism
9.0: Headache associated with noncephalic infection
9.1: Viral infection
9.2: Bacterial infection
9.3: Headaches related to other infection
10.0: Headache associated with metabolic disorder
10.1: Hypoxia

Headache Associated with Hypoxia

         Decompression Headache
          Headache Associated with High Altitude
10.2: Hypercapnia
10.3: Mixed hypoxia and hypercapnia
10.4: Hypoglycemia
10.5: Dialysis
10.6: Headache related to other metabolic abnormality
Adrenal Dysfunction
11.0: Headache or facial pain associated with disorder of cranium, neck, eyes, ears, nose sinuses, teeth, mouth, or facial or cranial structures
11.1: Cranial bone
              Paget’s Disease
11.2: Neck
11.3: Eyes

Ocular and Retrobulbar Pain Associated with Ocular Disease

Cornea and Sclera

Superficial Corneal Disease

Limbal Disease

Posterior Scleritis

Iris

Iritis

Mechanical Stimulation

Chemical Stimulation

Acute Angle Closure Glaucoma

Ciliary Body

Retina and Choroid

Optic Nerve

Orbit

Inflammation

Tumors

Trauma

Postoperative Pain

Ocular and Retrobulbar Pain Without Ocular or Orbital Disease

Syndromes of Ocular or Retrobulbar Pain with Intracranial Disease

Raeder’s Paratrigeminal Neuralgia: Ophthalmic Division Pain (Cluster Headache) with Oculosympathetic Palsy

Tolosa-Hunt Syndrome

Trigeminal Pain During and After Herpes Zoster Ophthalmicus
Headaches and other Ocular Conditions
Eyestrain

11.4 Ears

Facial Pain with Sixth Nerve Palsy (Gradenigo’s Syndrome)

11.5: Nose and sinuses
11.6: Teeth, jaws and related structures

Maxillary and Mandibular Bone Cavities

11.7: Temporomandibular joint disease
Temporomandibular joint syndrome (TMJ)
12.0: Cranial neuralgias, nerve trunk pain, and deafferentation pain
12.1: Persistent (in contrast to tic-like) pain of cranial nerve origin
         Atypical facial neuralgia
         Post-Traumatic Facial Pain
         Facial (Geniculate) Ganglion Neuralgia From Herpes Zoster: The Ramsay Hunt Syndrome

12.2: Trigeminal Neuralgia
         Occurrence
         Symptomatology
          Etiology and Pathology
          Differential Diagnosis
         Treatment Part One

         Treatment Part Two

12.3: Glossopharyngeal neuralgia
          Glossopharyngeal (Vagoglossopharyngeal) Neuralgia
12.4: Nervous intermedius neuralgia
12.5: Superior laryngeal neuralgia
12.6: Occipital neuralgia
         Occipital Neuralgia
          Eye Pain From Occipital Neuritis (Greater Occipital Neuralgia)
          Greater Occipital Nerve Block Technique
12.7: Central causes of head and facial pain other than tic douloureux
          Facial Pain From Brainstem and Thalamic Lesions

Other Signs of Intrinsic Pontine Tumor

Greater Auricular Neuralgia

Itching

          Dysesthesia and Paresthesia From Specific Disorders
          Trauma
          Toxic Reactions
          Diabetes Mellitus
           Miscellaneous Causes

13.0: Headache not classifiable
          SUNCT syndrome

          Chronic daily headache
          Cluster-Tic Syndrome
References Page One
References Page Two