Nausea is queasy, unsettled feeling in the stomach combined with an urge to vomit. Nausea and vomiting, or throwing up, are not diseases, but may be an indication of certain diseases. Some people experience motion sickness, which can bring on nausea; so can pregnancy, migraines, food poisoning and other conditions. See a doctor if you have been vomiting for over 24 hours and/or are dehydrated.Medication may be prescribed according to the underlying condition; however certain natural supplements may help lessen nausea, including ginger, apple extract and peppermint. Aromatherapy can be helpful in certain instances.