Racing heart. Shortness of breath. Dizziness. These could be anxiety—or they could be something else entirely. Here's how to tell the difference.
Common Anxiety Symptoms
- Racing or pounding heart
- Shortness of breath
- Chest tightness
- Dizziness or lightheadedness
- Sweating
- Trembling
- Nausea
- Feeling of unreality
- Fear of dying or losing control
- Numbness or tingling
Medical Conditions That Mimic Anxiety
Thyroid Problems
Hyperthyroidism (overactive thyroid) causes: rapid heartbeat, sweating, tremor, weight loss, heat intolerance, irritability. A simple blood test (TSH) can rule this out.
Heart Conditions
Arrhythmias, mitral valve prolapse, and other cardiac issues can cause palpitations and chest discomfort. Key differences from anxiety:
- Occurs during rest/sleep (anxiety usually has triggers)
- Associated with exertion
- Irregular heartbeat (not just fast)
- Fainting
Low Blood Sugar
Hypoglycemia causes shakiness, sweating, confusion, rapid heartbeat. Often occurs hours after eating or with diabetes medications.
Caffeine and Stimulants
High caffeine intake mimics anxiety perfectly. Also: energy drinks, pre-workout supplements, ADHD medications, decongestants.
Respiratory Conditions
Asthma and COPD can cause breathlessness that triggers (or is mistaken for) anxiety.
Other Conditions
- Anemia
- Menopause (hot flashes)
- Pheochromocytoma (rare adrenal tumor)
- Vestibular disorders (dizziness)
- Medication side effects
When to See a Doctor
See your doctor if:
- Symptoms are new and unexplained
- You have risk factors for heart disease
- Symptoms don't fit the pattern of anxiety
- You have other concerning symptoms (weight loss, fever)
- You haven't had a physical exam recently
Tests That Rule Out Medical Causes
- Basic blood panel (thyroid, blood sugar, electrolytes)
- EKG (heart rhythm)
- Chest X-ray if respiratory symptoms
- Blood pressure monitoring
- Holter monitor if irregular heartbeat
The Vicious Cycle
Here's the tricky part: health anxiety about these symptoms makes them worse. You feel a palpitation, worry it's your heart, which releases adrenaline, which causes more palpitations. Getting medical clearance can break this cycle.
The Bottom Line
Most anxiety symptoms are anxiety. But if you haven't had a recent physical, or your symptoms are new or atypical, get checked out. Once medical causes are ruled out, you can address the anxiety with confidence—knowing your heart and thyroid are fine.