Differential Diagnosis

The patient presents with headaches, nausea and vomiting (N/V), body aches, and photophobia (suggested by relief with darkness), which have been ongoing for 2 days. The patient has a history of migraines but reports that medications, including over-the-counter (OTC) Tylenol, have not provided relief.

• Single Most Likely Diagnosis

  • Migraine: Given the patient's history of migraines, the current symptoms of headache, N/V, and photophobia are consistent with a migraine episode. The fact that darkness helps suggests sensitivity to light, a common feature of migraines.

• Other Likely Diagnoses

  • Viral illness (e.g., influenza, viral gastroenteritis): The combination of body aches, headache, and N/V could suggest a viral illness. The lack of response to Tylenol does not rule out this diagnosis, as antipyretics may not fully alleviate all symptoms.
  • Tension headache: Although less likely given the photophobia and N/V, tension headaches can present with headache and body aches, and some patients may experience nausea.

• Do Not Miss Diagnoses

  • Subarachnoid hemorrhage: Although the patient's symptoms have been present for 2 days, which makes a subarachnoid hemorrhage less likely, the sudden onset of a severe headache (often described as "the worst headache of my life") with associated symptoms like N/V could suggest this diagnosis. It's critical to consider this, especially if there was an initial severe headache followed by ongoing symptoms.
  • Meningitis: Symptoms can include headache, fever, N/V, and photophobia. The absence of fever in the provided history does not rule out meningitis, as some patients may not present with fever, especially in viral meningitis.
  • Encephalitis: Similar to meningitis, encephalitis can present with headache, fever, altered mental status, and sometimes seizures. The patient's denial of taking any medications and the lack of relief from Tylenol could suggest a more severe underlying condition.

• Rare Diagnoses

  • Temporal arteritis: This condition typically affects older adults and presents with headache, scalp tenderness, jaw claudication, and visual disturbances. It's less likely given the patient's age is not specified, but it should be considered in older patients.
  • Cluster headaches: These are extremely painful headaches that occur in clusters or cycles, often waking the patient from sleep, and can be accompanied by autonomic symptoms like nasal congestion or eye watering. The patient's history of migraines and the description of symptoms do not strongly suggest cluster headaches, but they are worth considering in patients with severe, recurrent headaches.