Nausea is the feeling of wanting to vomit and may or may not be followed by vomiting. We all experience nausea several times in life – sometimes it occurs with certain acute diseases like food poisoning while at other times it occurs for no known reason. However, nausea in these instances is just a passing sensation. In some instances, nausea can be persistent occurring as recurrent episodes or remaining constant for long periods of time. It is these cases of chronic nausea that needs to be investigated intensively since nausea may be a sign of some underlying disease. Nausea is one of the common complaints among seniors and is at times due to unknown causes.
There are specific areas in the brain responsible for the sensation of nausea and the act of vomiting. These centers are stimulated mainly by irritation of the upper gut, especially the esophagus (food pipe) and stomach. In chronic cases of nausea, this may be a result of :
However, various substances in the bloodstream may also trigger these areas. Some of these may be endogenous, meaning it is produced within the body like hormones and waste products. This may be seen with :
Other substances are exogenous in that it is derived from the environment like medication and toxins. This includes :
Any inflammation or infection of the central nervous system (CNS) may also cause nausea as the relevant centers in the brain may be irritated. CNS conditions that may be responsible includes :
Nausea can also occur with other disorders that may be characterized by severe pain, with angina pectoris or during a heart attack and in depression of episodes of anxiety.
It is essential to identify the exact cause of chronic nausea before commencing treatment. Drugs known as antiemetics are effective in relieving nausea and vomiting but only serves as a means to control the symptoms. Once the cause is diagnosed, treatment can be directed at the underlying condition which when treated effectively will allow the nausea to subside.
Certain foods and drinks can serve as triggers or worsen existing nausea. Excluding these foods or substances from the diet is therefore necessary in managing long term nausea. The common cause in the elderly is related to medication side effects, associated with age-related reduction in nausea, with severe pain and as a result of chronic diseases. Proper management of the cause in these instances are necessary as antiemetics may prove to be of limited use in the long term.