What are the symptoms?

Someone withCVSwill go through a regular cycleof feeling ill, recovering, feeling well and then feeling ill again.

This cycle is made up of four phases:

1. Prodrome phase :

  • feeling that an episode is about to start
  • intense sweating and nausea for a few minutes to a few hours

2. Vomiting phase :

  • retching and vomitingthat often starts in the night or early morning
  • vomitingup to five or six times an hour for at least one hour, for up to 10days
  • may not be able to move or respond
  • other possible symptoms: abdominal pain, diarrhoea, fever, dizziness, headache, sensitivity to light, extremely pale skin, drowsiness or unresponsiveness, drooling or spitting excess saliva

3. Recovery phase:

  • vomiting and retching stop, and nausea subsides
  • recovery is gradual or immediate

4. Well phase:

  • a period of no symptoms until the prodrome phase starts again

The cycle tends to be regular and predictable: the same symptoms,starting at the same time of the day, for thesame durationeach time.

Content supplied by the NHS Website

Medically Reviewed by a doctor on 21 Dec 2018