Orofacial pain resembling hypnic headache: A case report

Abstract

The International Classification of Orofacial Pain (ICOP) classifies orofacial pain resembling primary headache as orofacial migraine and tension-type, trigeminal autonomic, and neurovascular orofacial pain. We used the ICOP classification style to make a diagnosis on a 76-year-old woman with orofacial pain, which developed only during sleep three times per week, caused awakening, and lasted 3–4 h without cranial autonomic symptoms or restlessness. Except for the pain area, her symptoms fulfilled the diagnostic criteria for hypnic headache. We diagnosed her with orofacial pain resembling hypnic headache. We should review the cases of such patients and classify them according to the ICOP.

Introduction

The first edition of the International Classification of Orofacial Pain (ICOP) is the first comprehensive and internationally accepted classification of orofacial pain. ¹ The ICOP was created based on the hierarchical design and classification style of the third edition of the International Classification of Headache Disorders (ICHD-3). ² Orofacial pain resembling primary headaches is defined by the ICOP as orofacial migraine, tension-type orofacial pain, trigeminal autonomic orofacial pain, or neurovascular orofacial pain. ¹

Hypnic headache, a rare primary headache disorder, is characterized by frequent recurring headache attacks that develop only during sleep, occurs for >10 days per month for >3 months, causes awakening, lasts from 15 min to 4 h, and is not accompanied by cranial autonomic symptoms or restlessness. ²

We report the case of a patient with orofacial pain, which developed only during sleep, occurred three times per week, caused awakening, lasted for 3–4 h, and was not accompanied by cranial autonomic symptoms or restlessness.

Case report

A 76-year-old woman presented with a 4-month history of nocturnal sore tongue (bilateral) and tonsillar fossa that awakened her from sleep. The attacks occurred three times per week, usually began between 3 a.m. and 4 a.m., and lasted for 3–4 h. The pain was diffuse, constant (nonpulsatile), and had moderate or severe intensity. She did not experience nausea, photophobia, phonophobia, ptosis, lacrimation, rhinorrhea, or a sense of restlessness or agitation. The pain intensity did not aggravate her physical activity. She used 200 or 400 mg acetaminophen once per week for severe pain and fell asleep approximately 10 min after using the medication. She did not exhibit loud snoring, episodes that led to breathing cessation during sleep, or excessive daytime sleepiness. She consulted a dentist, otolaryngologist, and a general physician; however, her pain did not resolve. She had no history of headache. Her medical history was remarkable for hypertension, hyperlipidemia, chronic gastritis, insomnia, cholecystectomy, and thyroidectomy. She regularly used 2.5 mg amlodipine, 2.5 mg rosuvastatin calcium, 10 mg lafutidine, 5 mg zolpidem tartrate, 75 µg levothyroxine sodium hydrate, and 1 µg alfacalcidol after breakfast. Her blood pressure had been well-controlled and was approximately 120–130/70–80 mmHg. When she woke up with pain, she confirmed that her blood pressure was in the usual range. She did not use any other medication or caffeinated beverage at bedtime. Interestingly, there was no family history of headache. The results from her neurologic and general examinations and the corresponding from magnetic resonance imaging of the brain were normal. Her body mass index was 25.7.

Sleep-associated secondary headache disorders were ruled out. Her pain attacks fulfilled the diagnostic criteria for hypnic headache, as defined by the ICHD-3, without pain area. The pain was not located in the head but in the orofacial area. Using the ICOP classification style, we diagnosed her pain attacks as orofacial pain resembling hypnic headache. Ramelteon was initiated at a dose of 8 mg at bedtime. Her pain attacks disappeared 2 weeks after initiating ramelteon therapy. She has been headache-free and without any adverse events for 6 months with ramelteon therapy.

Discussion

To the best of our knowledge, this is the first report of a patient with orofacial pain resembling hypnic headache. Orofacial pain resembling primary headaches is classified into three types: type 1, headache with facial pain during and usually ipsilateral to the headache attacks; type 2, headache attacks that have stopped and have been replaced by facial pain attacks of the same quality, length, and intensity and include the symptoms associated with the former headache; and type 3, de novo orofacial pain attacks without headache resembling the pain characteristics, duration, and intensity of one of the primary headache types with or without the symptoms associated with these headache types. ¹ Our case appeared to resemble type 3 orofacial pain. Orofacial pain resembling primary headache does not include orofacial pain resembling hypnic headache. We propose that orofacial pain resembling hypnic headache or other primary orofacial pain disorders should be added to the ICOP when similar cases are reported.

Lithium, caffeine, melatonin, and indomethacin have been reported to be effective against hypnic headache. ² Especially, our patient showed a satisfactory response to ramelteon. We previously reported that ramelteon immediately suppressed cluster headache attacks during sleep and resulted in no adverse effects. ³ Ramelteon is a highly selective melatonin MT1/MT2 receptor agonist that is used in insomnia therapy. ³ Interestingly, the mean half-life of 8 mg ramelteon dosage is longer than that of melatonin (1.4 h vs. 30–50 min). ³ After oral administration, ramelteon undergoes an extensive first-pass effect during hepatic metabolism. ³ The half-lives of the main metabolites, one of which is 20- to 100-fold more active than melatonin, range from 1 h to 3 h. ³ Arai reported a case of unilateral hypnic headache with rapid response to ramelteon. ⁴ This case occurred in an 81-year-old woman with hypnic headache. Treatment with 8 mg ramelteon at bedtime rendered her headache-free period without side effects for more than 6 months. Ramelteon is generally well-tolerated by elderly individuals; therefore, it may be a prophylactic option for patients with hypnic headache and orofacial pain resembling hypnic headache.

Clinical implications

• Orofacial pain can resemble hypnic headache.

• We should review the cases of such patients and classify them according to ICOP.