Nausea is an unpleasant sensation that is often considered as a precursor of vomiting. It is a painless condition where the person feels an unsettling discomfort which is often accompanied by vomiting.

Even if the condition is painless, if ignored, nausea can be an exhaustive symptom for more serious health conditions, which can eventually make way for periodic chest pains and other discomforts in the lower abdomen and the back of the throat.

Causes
Nausea is not a disease but a symptom of various health conditions. From morning sickness in pregnant women to sensitivity and motion, the causes for nausea are many.

Some of the most common causes are:

• Gastrointestinal disorders – Acute nausea can be caused because of the presence of one or more gastrointestinal disorders, such as functional dyspepsia, celiac disease, peptic ulcer, Crohn’s disease, hepatitis, and pancreatic cancer. This is one of the most common causes of nausea.
• Food poisoning – Food poisoning is another common cause of nausea and vomiting. This is caused because of the toxins produced by bacteria and virus in food. Nausea and vomiting usually occur between one to six hours after the consumption of unhealthy food and can last up to three days.
• Medication – Usage of certain medicines can also cause nausea. The most frequent case is with chemotherapy, where the patients experience acute nausea as a side effect. In order to minimize the risk, read the information about the medicines carefully and/or talk with the doctor before consuming it.
• Ulcer – Peptic ulcer is a term that is not alien for the average American. According to the statistics, approximately 4 million Americans have a peptic ulcer. It a serious condition of developing sores in the lining of the stomach, lower esophagus, or small intestine. When a person with ulcer consumes food, it causes sudden nausea and a burning sensation in the stomach.
• Pregnancy – A majority of pregnant women experience nausea or “morning sickness” during the initial stages of pregnancy. Cyclic vomiting syndrome, a condition associated with morning sickness, causes periodic nausea and vomiting. Though it is mostly mild and harmless, it might lead to a condition known as hyperemesis gravidarum that may require treatment.
• Motion sickness – Another most common cause of nausea is motion sickness. This happens when the visually perceived movement conflicts with the messages sent to the brain. Another condition is vertigo, where a person feels as if they or the object around them are moving or spinning. This can lead to nausea, dizziness, and vomiting.

Some of the other medical conditions that may cause nausea are:

• Heart attack
• Depression
• Fever
• Milk allergy
• Liver failure
• Ear infection

When to see a doctor?
There is no particular sign or symptom that decides when to see the doctor or seek healthcare when it comes to nausea. But, if the condition stays for 2 or 3 days and a person is unable to consume food, a visit to the doctor would be preferable. A person having a troublesome history with nausea must undergo the basic laboratory tests.

One can seek medical help if one or more of these symptoms accompany nausea:

• Chest pain
• Blurred vision
• Severe abdominal pain or cramping
• Severe headache
• Dehydration
• Dizziness
• Blood in vomit
• Breathing difficulty
• Stiff neck
• If the person is unable to eat or drink for more than 12 hours because of nausea