Differential Diagnosis for Nausea
The following is a differential diagnosis for a patient presenting with nausea, categorized for clarity and prioritization.
Single most likely diagnosis
- Gastroenteritis: This is often the most common cause of nausea, typically resulting from a viral or bacterial infection leading to inflammation of the stomach and intestines. The justification for this being the single most likely diagnosis is its high prevalence and the common presentation of nausea as a primary symptom.
Other Likely diagnoses
- Food poisoning: Similar to gastroenteritis, food poisoning from consuming contaminated or spoiled food can lead to nausea, vomiting, and other gastrointestinal symptoms.
- Viral gastroenteritis (e.g., norovirus): Highly contagious and common, especially in closed environments like cruise ships or hospitals.
- Motion sickness: A common condition triggered by conflicting signals sent to the brain by the senses of sight, hearing, and touch, often during travel.
- Pregnancy: Morning sickness is a classic symptom of early pregnancy, affecting a significant number of pregnant women.
- Medication side effects: Many medications can cause nausea as a side effect, including antibiotics, pain relievers, and chemotherapy.
Do Not Miss (ddxs that may not be likely, but would be deadly if missed)
- Appendicitis: Although less common, appendicitis can present with nausea and vomiting, and missing this diagnosis can lead to severe consequences, including perforation and peritonitis.
- Myocardial infarction (heart attack): In some cases, especially in women, nausea and vomiting can be symptoms of a heart attack, making it crucial not to overlook this possibility.
- Pancreatitis: Inflammation of the pancreas can cause severe nausea and vomiting, among other symptoms, and requires prompt medical attention.
- Intestinal obstruction: A blockage in the intestine can lead to severe nausea, vomiting, and constipation, and is a medical emergency.
Rare diagnoses
- Brain tumors: Certain tumors, especially those in the brainstem or cerebellum, can cause nausea and vomiting due to increased intracranial pressure or direct effects on the vomiting centers.
- Meningitis: Inflammation of the protective membranes covering the brain and spinal cord can cause nausea, vomiting, headache, and stiff neck.
- Porphyrias: A group of rare genetic disorders that can cause a variety of symptoms, including nausea, vomiting, and abdominal pain.
- Addison's disease: A rare disorder of the adrenal glands can lead to nausea, vomiting, and other systemic symptoms due to insufficient production of adrenal hormones.