Many things can lead to random nausea. Most commonly, nausea is the result of a stomach infection, but it can also be associated with things like hormone imbalances, sleep deprivation, brain injuries, and stress. If no obvious cause for nausea can be identified, it is advisable to see a doctor, as feeling nauseous can be a sign of a serious medical complication. A doctor can perform a workup to learn why a patient is feeling ill and develop a treatment plan for addressing the underlying cause.

Random nausea is often associated with a stomach infection. Whether mild or severe, if bacteria, viruses, and other organisms get into the gastrointestinal tract, patients often feel sick to their stomachs. In addition, severe infections elsewhere in the body can lead to nausea. Certain medications like chemotherapy, drugs used for general anesthesia, and antibiotics can also cause random nausea. These side effects are usually disclosed ahead of time so patients know to expect them.

Disequilibrium associated with balance disorders can be a cause, as can fatigue, stress, or extreme emotional distress. Some people with anxiety disorders and other psychiatric conditions develop random nausea as a symptom. Hangovers, where people feel ill after drinking too much alcohol, are also associated with nausea, and people can also feel sick to their stomachs as a result of eating or drinking in excess, or not getting enough food and water. Certain conditions like diabetes are also linked with an increased risk of nausea.

Hormone imbalances such as those associated with pregnancy are linked with nausea. People with odor sensitivity can also feel sick to their stomachs when they are exposed to strong odors, and nausea can also be a symptom for people with conditions like post traumatic stress disorder. When they experience panic attacks, they can feel sick or vomit. People can also develop nausea as a result of motion sickness while traveling on cars, boats, trains, or planes, and motion sickness can onset at any time. Head injuries can also cause nausea and it may emerge minutes, hours, or even days after the initial injury.

When someone is feeling nauseous, it can help to lie down in a calm environment and drink something carbonated to settle the stomach. The cause of the random nausea should be identified to determine if more treatment is needed. Someone feeling sick after surgery, for example, just needs to rest while the body eliminates the last of the anesthesia. Someone feeling nauseous for no apparent reason might be experiencing extreme dehydration, kidney failure, or other serious medical complications that need to be treated.