Nausea is a feeling of discomfort and uneasiness in the stomach. It is a diffuse feeling and is not focused on a single area of the stomach, and it is mostly painless. The feeling may spread from the upper abdomen to the chest and back. Nausea is often accompanied by retching and vomiting. The feeling lasts for a short time, but in cases where it is prolonged, it can be debilitating. Although not a disorder in itself, it is a symptom of a number of conditions. Here are some of the most common causes of nausea:
- Early pregnancy
Approximately 70% of women experience nausea during the first trimester, and sometimes also into the second trimester. Commonly called morning sickness, this uncomfortable feeling is not harmful to the mother or the baby, and it is often one of the earliest signs of pregnancy. Some people believe that nausea is an indication of a healthy pregnancy if it is not accompanied by other undesirable symptoms. - Sensitivity to odor
Some people experience nausea and report smelling a strange smell that others cannot perceive. It is possible that people with migraine headaches have such episodes, and strong unpleasant smells can also trigger nausea and vomiting. - Motion sickness
Motion sickness is a common ailment that affects people while traveling by car, bus, train, airplanes, and especially boats. Motion sickness happens when the sensory inputs from the various senses do not match up while traveling. The symptoms are nausea, dizziness, and cold sweats, accompanied by vomiting at times. - Overeating
Nausea and vomiting are caused by stomach rebelling against the overdose of food ingested. - Stress
Social anxiety, performance anxiety, overexcitement, fear, and stress can cause nausea. Such stress factors can generate a range of feelings, from a butterfly belly to sweating and the urge to use the bathroom. - Intense pain
Any pain that is connected to the digestive tract can, in some cases, radiate to the back, and the cause of the pain may result in nausea. - Ingesting excess alcohol or other toxins
Similar to overeating, consuming substances that the stomach cannot tolerate will generate nauseous feelings and can lead to vomiting. Different substances affect people differently, as not everyone is used to consuming the same type of food or beverages. - Food poisoning
Food poisoning is a result of consuming contaminated food. Invariably, contamination is caused by disease-causing organisms that exist in the food, and nausea is a common symptom when a person has food poisoning. - Certain infections
Infections that mostly affect the digestive system, like hepatitis A, B, and C, giardiasis, Helicobacter pylori, iron poisoning, mumps, sickle cell disease, and Ascaris worms can also lead to nausea. - Ulcers
Ulcers in the stomach cause abdominal pain, followed by bloating, nausea, vomiting, and heartburn. - Appendicitis
An inflamed appendix can cause symptoms like sudden abdominal pain near the belly button, nausea, vomiting, loss of appetite, and constipation. - Bowel obstruction
This is a disorder indicated by abdominal pain, bloating, cramps, nausea, and vomiting, accompanied by fever. - Heart attacks
Nausea and vomiting can be signs of an imminent heart attack. There are studies that suggest that the complicated interactions between the brain, stomach, and vagus nerve cause these symptoms before a heart attack occurs. - Brain tumor
Nausea can be one of the symptoms of some tumors like medulloblastoma. - Cancer
Tumors in the esophagus, stomach, or colon can cause bowel obstruction, leading to nausea and vomiting. Nausea can also be a result of cancer present in the lining of the abdominal cavity, the peritoneum. It commonly affects those undergoing treatment for cancer, both chemotherapy and radiation therapy. - Certain medications
Medications like aspirin, non-steroidal anti-inflammatory drugs (NSAIDs), antibiotics, erythromycin, and some blood pressure medications are known to cause nausea.
