Differential Diagnosis for Metallic Taste

• Single most likely diagnosis
  • Upper respiratory infection: A common cause of metallic taste due to the inflammation and congestion in the nasal passages and sinuses, which can affect the sense of taste.
• Other Likely diagnoses
  • Medication side effects: Certain medications, such as antibiotics, antihistamines, and decongestants, can cause a metallic taste as a side effect.
  • Gingivitis or periodontal disease: Inflammation of the gums can lead to changes in taste, including a metallic taste.
  • Sinusitis: Inflammation of the sinuses can cause a metallic taste due to the close proximity of the sinuses to the taste buds.
  • Pregnancy: Some women experience a metallic taste during pregnancy, possibly due to hormonal changes.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Heavy metal poisoning (e.g., lead, mercury, arsenic): Exposure to heavy metals can cause a range of symptoms, including a metallic taste, and can be life-threatening if not treated promptly.
  • Neurological disorders (e.g., multiple sclerosis, Parkinson's disease): Certain neurological conditions can affect the sense of taste, including causing a metallic taste.
  • Cancer (e.g., head and neck cancer): In rare cases, a metallic taste can be a symptom of cancer, particularly head and neck cancer.
• Rare diagnoses
  • Sjögren's syndrome: An autoimmune disorder that can cause dry mouth and changes in taste, including a metallic taste.
  • Bell's palsy: A condition that causes facial paralysis, which can affect the sense of taste and lead to a metallic taste.
  • Zinc deficiency: A deficiency in zinc can cause changes in taste, including a metallic taste.