Differential Diagnosis

Given the information that sildenafil was taken the night prior and an event occurred at around 3pm the next day, we can consider the following differential diagnoses:

• Single most likely diagnosis

  • Prolonged erection or priapism: This is a known side effect of sildenafil, especially if the medication was taken in excess or if the individual has certain underlying health conditions. The timing (occurring the next day) fits within the window of sildenafil's effects.

• Other Likely diagnoses

  • Headache: Sildenafil is known to cause headaches as a side effect, which could occur within this timeframe.
  • Flushing: Facial flushing is another common side effect of sildenafil, which could still be present or occur the next day.
  • Gastrointestinal upset: Some individuals may experience nausea, dyspepsia, or diarrhea after taking sildenafil, which could be related to the event described.

• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)

  • Myocardial infarction (MI) or heart attack: Although less common, sildenafil can increase the risk of MI, especially in individuals with pre-existing heart disease. The timing and symptoms could potentially overlap.
  • Stroke: Similar to MI, there is a small increased risk of stroke associated with sildenafil use, particularly in vulnerable populations.
  • Severe hypotension: Sildenafil can cause a drop in blood pressure, which, although rare, could lead to severe hypotension, especially when combined with other vasodilators or in susceptible individuals.

• Rare diagnoses

  • Non-arteritic anterior ischemic optic neuropathy (NAION): A rare condition associated with sudden vision loss, which has been linked to sildenafil use, although the mechanism is not fully understood.
  • Hearing loss: There have been reports of sudden hearing loss associated with sildenafil, which, although rare, warrants consideration in the differential diagnosis.
  • Seizures: Extremely rare, but there have been case reports of seizures potentially associated with sildenafil use, particularly in individuals with a history of seizure disorders.