Nausea is the sensation of wanting to vomit and may or may not precede actual vomiting. In chronic nausea, vomiting may occur intermittently, especially when exacerbated by certain foods, motion, hunger or stress. Diagnosing the cause of chronic nausea depends on the identifying the onset of the nausea episode(s) as well as considering concomitant signs and symptoms.
Chronic nausea itself may be constant, where it does not allay and sometimes continues even while sleeping, or it may be recurrent, where it occurs as episodes that tend to persist for certain periods only to resolve spontaneously. Trigger or exacerbating factors may vary.
Nausea is often associated with a lack of appetite, regurgitation frequently, vomiting occasionally, stomach ache or abdominal pain. Dizziness, fainting, changes in bowel movement or urination could be related to the cause of the chronic nausea or may occur as a result of persistent vomiting leading to complications like dehydration.
Causes of Chronic Nausea
The most common cause of nausea is upper gastrointestinal conditions like acid reflux, gastritis or a peptic ulcer. This is common in both men and women. In women of childbearing, pregnancy needs to be ruled out in every case before considering other causes, especially if there is morning peaks of nausea with vomiting (morning sickness), breast tenderness and amenorrhea.
In gastrointestinal conditions, vomiting is often present, the nausea tends to aggravate after eating or when hungry, and other symptoms like stomach bloating, excessive belching and sometimes diarrhea is present.
- Acid reflux (GERD – chronic)
- Non-ulcer dyspepsia (indigestion)
- Chronic gastroenteritis
- Food poisoning
- Peptic ulcer
- Gastrointestinal obstruction (Delayed Gastric Emptying, Blocked Bowel) – projectile vomiting is common
- Hiatal hernia
- Food intolerances
- Chronic pancreatitis
A number of hormone-related conditions may cause nausea in girls and women. It is usually episodic – mornings in pregnancy, before periods in premenstrual syndrome. However, it can be persistent even in these cases.
- Premenstrual syndrome (PMS)
- Medication : contraceptives, HRT (hormone replacement therapy), fertility drugs
Central Nervous System
CNS disorders that result in nausea often present with other symptoms like dizziness and/or headaches. Poor concentration, memory or impaired cognition accompanying nausea should always prompt immediate medical attention.
- Head trauma
- Intracranial hemorrhage
- Raised intracranial pressure
- Infections – meningitis, encephalitis
Drugs, Toxins and Poisons
Nausea is a common side effect of most medication. In may occur as a result of stimulating the chemoreceptor trigger zone (CTZ) or due to gastric irritation (gastritis). Among the more frequently used medication, certain NSAIDs and antibiotics are the more common causative agents. With drugs, toxins and poisons, the nausea may resolve once the substance in question is discontinued.
- Prescription drugs
- Toxins – microbial (food poisoning)
- Poisons – insecticides, pesticides, heavy metals
- Alcohol abuse
- Nicotine replacement therapy (NRT)
Systemic and Other Conditions
- Diabetes, especially diabetic ketoacidosis
- Kidney failure
- Liver failure
- Severe pain
- Psychogenic – anxiety, depression