A 51-year-old woman working as a financial consultant was admitted to our headache outpatient clinic with a complaint of continuous headache for 2 years. She described the characteristics of her headache as a heavy sensation and pressure involving the whole head. The severity was mild to moderate and she did not describe worsening with physical activity. When said there were no accompanying symptoms such as nausea, vomiting, and/or photo-phonophobia. She was taking painkiller pills containing metamizole sodium 500 mg 4–6 times per month, each time one or two tablets without any significant benefit.

Before admission to our center, she visited many neurologists, by most of whom she was told to have some kind of a tension-type headache. Also a number of other physicians came up with several other diagnoses. Several antidepressants, mostly selective serotonin reuptake inhibitors, were prescribed as preventive treatment. However, most of these drugs had either caused side effects, preventing her to continue the treatment, or were ineffective. Consequently, she discontinued all long-term preventive treatments for her headache.

She emphasized that the onset of her headache was associated with a lawsuit while she had been working as a manager in a foundation company, and the severity of her headache increased in every inquiry. She also mentioned that her headache starts when she considers that she could not adequately express herself. Interestingly, abdominal, chest, and back pain also accompanies the headache simultaneously.

Her past history was significant for either headache or back pain or both since university years, worsening or improving at different times in her life. She received different diagnoses for this painful syndrome. However, over the years despite extensive investigations, no associated underlying organic disorder or disease could be found. She was also referred to internal medicine because of gastrointestinal symptoms such as abdominal pain, nausea, and dyspepsia. She received a diagnosis of gastritis, but endoscopic study did not reveal any significant abnormality. Her neurological examination was normal. Cranial magnetic resonance imaging did not reveal any abnormality. She was on valsartan hydrochlorothiazide and amlodipine treatment for hypertension and insulin and oral antidiabetics for diabetes mellitus. She has no known allergies. She is the second of five siblings, and there is no remarkable medical history in others with the exception of an elder brother who recently had an episode consistent with transient global amnesia. Her mother died because of breast cancer, and she reported dying of her father at old age. She does not smoke and does not use alcohol regularly.

In her physical examination, there was tenderness bilaterally in the regions of the great occipital nerve, upon which we performed bilateral great occipital nerve blockade with methylprednisolone and lidocaine 2 %. The patient’s headache did not improve after this procedure.

We referred the patient for a psychological evaluation because of the strong relationship between the onset and worsening of her headache with stressful events. The psychiatrist’s impression was that she had a somatoform disorder and passive aggressive behavior disorder according to DSM-IV criteria. He suggested behavioral psychotherapy for treatment. Currently she continues her psychotherapy and her headaches improved greatly.

According to the DSM-IV criteria, which is currently accepted by ICHD-3, somatization disorder is defined as a chronic disorder characterized by a history of many physical complaints beginning before age 30 years that occur over a period of several years and result in treatment being sought or significant impairment of functioning. Physical symptoms must include 4 pain symptoms, 2 gastrointestinal symptoms, 1 sexual symptom, and 1 pseudo-neurological symptom, and these symptoms should not to be attributed to any medical condition. However, in the DSM-V, the new DSM version which was published in 2013, diagnoses of somatization disorder, hypochondriasis, pain disorder, and undifferentiated somatoform disorder were deleted, and “somatoform disorders” are now called somatic symptom and related disorders.

Somatic symptoms include stomach pain, back pain, extremity pain, menstrual problems (female), sexual problems, headaches, chest pain, dizziness, fainting, palpitations, dyspnea, bowel problems, nausea, indigestion, fatigue, and insomnia. The occurrence of these somatic symptoms tends to increase by chronification of headache regardless of the type of headache, and also patients who have frequent severe attacks have more somatic symptoms than patients with infrequent attacks. Besides these observations, it has been emphasized that psychiatric comorbidity shows a significant impact on the occurrence of somatic complaints.

It is still controversial whether headache attributed to somatization disorder is due to a psychiatric disorder or as a result of bioorganic cause. The interaction of cognitive and perceptual processes with behavioral, affective, and biological changes has been considered as the main factor of somatic symptoms by authors arguing biological process. Based on signal-filtering model, somatoform disorders can be understood as disorders in the perception of bodily signals. These (mis)perceptions may be explained by this model. In signal-filtering model of somatoform disorders, possible psychobiological and psychological influences are grouped to signal amplifying (over-arousal, distress, chronic hypothalamic-pituitary-adrenal axis, physical deconditioning, sensitization) and signal filtering (selective attention, infections, anxiety, depressive mood, lacking distraction). In addition to signal-filtering model, although there is still lack of adequate evidence, the endocrine system, immunological system, monamino acid neurotransmitters and the involvement of the nucleus caudatus have been suggested to play a role in developing somatoform symptoms.