The cause of<unk>  has not been determined and there are no diagnostic tests for<unk> . Several other medical conditions, such as cannabinoid hyperemesis syndrome (CHS), can mimic the same symptoms, and it is important to rule these out. If all other possible causes have been excluded, a diagnosis of<unk>  using Rome criteria by a physician may be appropriate. Once formal investigations to rule out gastrointestinal or other causes have been conducted, these tests do not need to be repeated in the event of future episodes. Diagnostic criteria Although there are differences between early-onset<unk>  (babies and children) and late-onset<unk>  (in adults), there are established criteria to aid in diagnosis of<unk> , namely: # A history of three or more periods of intense, acute nausea and unremitting<unk> , as well as pain in some cases, lasting hours to days and even weeks or months # Intervening symptom-free or reduced-symptom intervals, lasting weeks to months # There are repeated cycles of periods (of varying duration) with intense/acute nausea, with or without<unk> , with or without severe pain, followed by periods of reduced symptoms, followed by gradual increase in<unk>  symptoms until it peaks (peak intensity is generally relative to cycle intensity). # Exclusion of metabolic, gastrointestinal, genitourinary or central nervous system structural or biochemical disease, e.g., individuals with specific physical causes (such as intestinal malrotation)
Cyclic vomiting syndrome
Cannabinoid hyperemesis syndrome
Ichthyoallyeinotoxism
Geophagia
Bloom syndrome
Aerophagia
Jamaican vomiting sickness
Mallory–Weiss syndrome