Cyclic Vomiting Syndrome (CVS) (cont.)

If the condition is not treated, attacks typically occur four to 12 times per year. Between episodes, vomiting is absent, and nausea is either absent or much reduced. However, many affected people experience other symptoms during and between episodes, including pain, digestive disorders such as gastroesophageal reflux and irritable bowel syndrome, and fainting spells (syncope). People with cyclic vomiting syndrome are also more likely than people without the disorder to experience depression, anxiety, and panic disorder. It is unclear how these health conditions are related to nausea and vomiting.

Cyclic vomiting syndrome is generally considered to be a variant of migraines, which are severe headaches often associated with pain, nausea, vomiting, and extreme sensitivity to light and sound. Many people with cyclic vomiting syndrome have a family history of migraines, and attacks of nausea and vomiting may be replaced by migraine headaches as an affected person gets older.

Most people with cyclic vomiting syndrome have normal intelligence, although some affected people have experienced developmental delay or intellectual disability, muscle weakness (myopathy), and/or seizures. People with these additional features are said to have cyclic vomiting syndrome plus.

Source: MedicineNet.com
http://www.medicinenet.com/cyclic_vomiting_syndrome_cvs/article.htm