A patient history of otherwise unexplained symptoms in two or more organ/systems:

Constitutional:

fatigue

fevers

subjective or objective hyperthermia or hypothermia

flushing

sweats

increased or decreased appetite

weight loss or gain

migratory pruritis

plethora or pallor

chemical/physical sensitivities (often "odd")

poor healing

Pulmonary:

airway inflammation at any level

dyspnea (mild, episodic, "just can't catch a deep breath") or "air hunger"

cough

quick or shallow breathing

sleep apnea regardless of weight

Psychiatric:

depression, anger, irritability, mood lability

anxiety disorders

attention deficit/hyperactivity disorders

Endocrinologic and Metabolic:

abnormal electrolytes or liver function tests

hypo or hyperthyroidism, lability of thyroid function

dyslipidemia

impaired glucose control

hypo or hyperferritinemia

nutritional deficiencies, micronutrient deficiencies

delayed puberty

adrenal dysfunction

Neurologic:

headaches

sensory neuropathies (commonly episodic/migratory paresthesias in extremeties)

seizure disorders or "pseudoseizures"

dysautonomias

episodic weakness

cognitive function difficulties (memory, concentration, word-finding)

dyssomnias (insomnia, frequent waking, hypersomnolence, non-restorative sleep, restless legs, sleepwalking or sleep talking, paralysis, night terrors)

sensitivity to sound

tremors

sensation of internal “shaking”

Cardiovascular:

chest pain

palpitations

presyncope or syncope

hypotension

hypertension

blood pressure lability

odd heart failure (example takosubo)

migratory edema

tachycardia

bradycardia

atherosclerosis

various heart rhythm abnormalities

Kounis syndrome (allergic angina)

vascular anomalies

Genitourinary:

frequency

urgency

painful urination

kidney disease

endometriosis

chronic back/flank/abdominal pain

infertility

miscarriages

decreased libido

vulvodynia

vaginitis (often misdiagnosed as infectious)

painful and/or irregular dysmenorrhea or menorrhagia

a variety of challenges with sexual intercourse

interstital cystitis (often misdiagnosed as infection, culture-negative)

recurrent infections resulting from IC

Gastrointestinal and Esophageal:

dyspepsia

dysphasia

globus sensation

gastroesophageal reflux

nauusea

vomiting

diarrhea and/or constipation (often alternating)

gastroparesis

feeling of fullness

angioedema

dysphagia

bloating/gas (sometimes extreme)

migratory abdominal pain

malabsorption

cholecystectomy is common (gallbaldder removal often yielding normal pathology)

Oral/Oropharyngeal:

Pain, burning, or irritation

leukoplakia

ulcers

angioedema

dysgeusia

dental and/or periodontal inflammation/decay despite hygiene

Otologic/Osmic:

Infectious or sterile otitis externa and/or media

hearing loss

tinnitus

dysomia

vertigo

coryza (rhinitis)

post-nasal drip

congestion

epistaxis (nose bleeds)

Hematologic:

easy bruising

abnormalities in clotting time

vasculitis

polycythemia or anemia (typically mild)

leukocytosis or leukopenia (typically mild)

monocytosis or eosinophilia or basophilia (typically mild)

thrombocytosis or thrombocytopenia (typically mild)

arterial and/or venous thromboembolic disease

Immunologic:

hypersensitivity reactions

increased risk for malignancy

autoimmunity

impaired healing

increased susceptibility to infection

increased or decreased levels of immunoglobulin of any isotype

monoclonal gammopathy of undetermined significance

Hepatic:

elevated transaminases

hepatomegaly (enlarged liver)

Lymphatic:

Adenopathy (usually sub-pathologic and spontaneously waxing/waning in size, frequently migratory)

adenitis

splenitis (typically mild)

Dermatologic:

dermatographism

rashes/lesions of many sorts

angioedema

alopecia

urticaria

onychodystrophy (brittle/ longitudinally ridged nails)

Musculoskeletal/Connective Tissue:

muscle pain (migratory)

joint pain (migratory)

joint laxity/hypermobility

osteopenia/osteoporosis/osteosclerosis

other tissue growth or development abnormalities

Also particularly note in medical history any presence of:

anaphylactoid reactions

idiopathic “panic attacks”

livedo reticularis

diagnosis or suspicion of eating disorders

autism spectrum disorder

unexpected or paradoxical responses to medications

issues with radiology, electromagnetic fields or other common mast cell triggers like vibration, sun, sweat, hormonal changes, alcohol, spicy foods, exercise, pressure changes, and so on

*Symptoms appearing after skin allergy testing, Covid-19 or other illness, pregnancy, medical procedures, or other major triggers are often particularly helpful red flags for this disorder.