What is the initial approach to a patient presenting with non-rotatory dizziness and vomiting?

Initial Approach to Non-Rotatory Dizziness with Vomiting

Begin by categorizing the presentation using timing and triggers rather than symptom quality, as this approach is more diagnostically accurate than relying on patient descriptions of "dizziness" type. 1, 2

Immediate Risk Stratification

First, exclude life-threatening causes that require urgent intervention:

• Acute coronary syndrome – Non-rotatory dizziness with vomiting can be an atypical presentation of ACS, particularly in women, elderly, and diabetic patients, often accompanied by diaphoresis and upper body discomfort 3
• Posterior circulation stroke – Up to 75-80% of patients with posterior circulation infarction causing acute vestibular syndrome lack focal neurologic deficits initially, making this a critical diagnostic pitfall 1, 4
• Increased intracranial pressure – Consider if accompanied by severe headache, altered mental status, or progressive neurologic symptoms 3
• Metabolic emergencies – Severe electrolyte disturbances, diabetic ketoacidosis, or adrenal crisis can present with non-specific dizziness and vomiting 3, 5

Timing-Based Differential Diagnosis

Acute Persistent Symptoms (Days to Weeks)

If symptoms are constant and have been present for days:

• Gastroparesis – Nausea, vomiting, and postprandial fullness without rotatory vertigo; most common in diabetics with long-standing type 1 diabetes and other complications (20-40% prevalence) 3
• Vestibular neuritis/labyrinthitis – Continuous severe non-rotatory imbalance with nausea/vomiting, but typically patients describe some sense of motion 1, 4
• Medication toxicity – Leading cause of chronic vestibular syndrome; review antihypertensives, sedatives, anticonvulsants, and psychotropic drugs 1
• Cyclic vomiting syndrome (CVS) – Stereotypical episodes of severe retching and vomiting lasting hours to days, often with abdominal pain and requiring sedation for relief 3

Episodic Symptoms (Minutes to Hours)

If symptoms come and go unpredictably:

• Vestibular migraine – Episodes lasting minutes to hours with headache, photophobia, and phonophobia; no auditory symptoms 1, 4
• Metabolic disorders – Hypoglycemia, uremia, or electrolyte disturbances causing intermittent symptoms 3, 5
• Cardiac arrhythmias – Presyncope with nausea, particularly if triggered by exertion 3

Chronic Symptoms (Weeks to Months)

If symptoms are persistent or progressive:

• Medication adverse effects – Most common reversible cause; systematic review is essential 1, 6
• Psychiatric disorders – Anxiety, panic disorder, and depression are common causes of chronic non-rotatory dizziness with associated nausea 1, 5
• Functional dyspepsia – Chronic upper abdominal discomfort with nausea and postprandial fullness; 25-40% have delayed gastric emptying 3
• Posterior fossa mass – Progressive symptoms with neurologic signs warrant urgent imaging 1

Critical History Elements

Focus on these specific details rather than vague descriptions:

• Timing pattern – Acute vs. episodic vs. chronic; duration of individual episodes 1, 2

• Triggers – Positional changes, food intake, medications, stress 3, 2

• Associated symptoms:

  • Auditory symptoms (tinnitus, hearing loss, aural fullness) suggest peripheral vestibular pathology, NOT typically present with non-rotatory dizziness 1, 4
  • Postprandial fullness, early satiety suggest gastroparesis 3
  • Severe abdominal pain with vomiting suggests CVS or GI obstruction 3
  • Chest discomfort, dyspnea, diaphoresis mandate ACS evaluation 3
  • Headache, photophobia suggest vestibular migraine or increased ICP 1
  • Neurologic symptoms (diplopia, dysarthria, dysphagia, ataxia) indicate central pathology 1, 4

• Medication review – Systematically review ALL medications, as this is the most common and reversible cause 1, 6

• Vomiting characteristics – Differentiate true vomiting from regurgitation, rumination, or bulimia; timing relative to meals; presence of bile or blood 3, 5

Physical Examination Priorities

Perform targeted examination based on history:

• Vital signs – Orthostatic hypotension, fever, tachycardia, hypertension 3, 5
• Cardiovascular – Arrhythmias, murmurs, signs of heart failure 3
• Abdominal – Distension, tenderness, palpable masses, succussion splash (gastroparesis), "olive" mass (pyloric stenosis in infants) 3
• Neurologic – Cranial nerves, cerebellar signs, gait assessment, Romberg test 1, 4
• HINTS examination – Only if true vertigo is present; unreliable when performed by non-experts 1

Critical pitfall: A normal neurologic examination does NOT exclude posterior circulation stroke in patients with acute vestibular symptoms 1, 4

Initial Diagnostic Approach

Laboratory Testing

Order selectively based on clinical suspicion:

• Basic metabolic panel – Electrolytes, glucose, renal function for suspected metabolic causes 5
• Complete blood count – If infection or anemia suspected 5
• Troponin and ECG – If any concern for ACS, especially in high-risk patients 3
• Pregnancy test – Mandatory in all women of childbearing age 5
• Thyroid function, cortisol – If endocrine disorder suspected 3, 5

Note: Routine blood tests are NOT indicated for straightforward peripheral vestibular disorders 7

Imaging Strategy

MRI brain without contrast is indicated for: 1

• Focal neurologic deficits
• Severe postural instability out of proportion to symptoms
• Age >50 with vascular risk factors and acute vestibular syndrome
• Progressive symptoms suggesting mass lesion
• New severe headache
• Failure to respond to appropriate treatment

CT head has very low yield (<1%) for isolated dizziness and misses most posterior circulation infarcts 1, 7

Abdominal imaging (plain radiograph initially): 3

• Suspected bowel obstruction
• Acute abdominal process
• Persistent vomiting in infants

Gastric emptying scintigraphy (4-hour study): 3

• Suspected gastroparesis after excluding obstruction
• Must be performed for 4 hours (not 2 hours) for accuracy

Management Approach

Gastroparesis (if confirmed)

• Dietary modifications – Small, frequent meals; low fat and fiber 3
• Prokinetic agents – Metoclopramide (with caution regarding tardive dyskinesia risk) 3
• Antiemetics – Ondansetron, promethazine 3
• Glycemic control – Critical in diabetic patients 3

Cyclic Vomiting Syndrome

• Abortive therapy – Sumatriptan (nasal spray or subcutaneous) plus ondansetron (sublingual); sedation with benzodiazepines or promethazine 3
• IV fluids with dextrose – Essential during acute episodes 3
• Non-narcotic analgesia – IV ketorolac preferred over opioids 3
• Prophylactic therapy – Consider after diagnosis established 3

Medication-Induced

• Remove offending agent – Most effective intervention 1, 6
• Adjust doses – If medication cannot be discontinued 1

Vestibular Migraine

• Migraine prophylaxis – Beta-blockers, tricyclic antidepressants, topiramate 1
• Lifestyle modifications – Trigger avoidance, sleep hygiene 1

Empiric Antiemetic Therapy (when cause unclear)

• Ondansetron – 4-8 mg PO/IV; sublingual formulation available 3, 6
• Promethazine – 12.5-25 mg PO/PR/IV; sedating, useful for inducing rest 3, 6
• Metoclopramide – 10 mg PO/IV; prokinetic effect beneficial if gastroparesis suspected 3, 6

Red Flags Requiring Urgent Evaluation

Any of these mandate immediate imaging and specialist consultation: 1

• Focal neurologic deficits
• Sudden severe headache
• Inability to stand or walk
• Downbeating or direction-changing nystagmus
• Altered mental status
• Signs of increased intracranial pressure
• Chest pain with hemodynamic instability
• Severe abdominal pain with peritoneal signs

Common Diagnostic Pitfalls

• Assuming normal neurologic exam excludes stroke – Most dangerous error; posterior circulation strokes frequently lack focal deficits initially 1, 4
• Relying on patient's description of symptom quality – "Dizziness" descriptions are unreliable; focus on timing and triggers instead 1, 2
• Ordering CT instead of MRI – CT misses most posterior circulation pathology 1, 7
• Failing to perform systematic medication review – Most common reversible cause of chronic symptoms 1, 6
• Overlooking ACS in atypical presentations – Particularly in women, elderly, and diabetics who may present with isolated nausea/vomiting and non-specific dizziness 3
• Performing 2-hour gastric emptying studies – Inaccurate; 4-hour studies required 3