Differential Diagnosis of Spontaneously Improving Facial and Arm Weakness

Immediate Assessment Priority

The American Heart Association recommends that acute ischemic stroke be considered immediately when facial weakness and arm weakness occur together with sudden onset, requiring emergency evaluation within minutes to hours, not days 1, 2
The American College of Cardiology suggests ruling out transient ischemic attack (TIA) or stroke with early recanalization as the highest mortality/morbidity risk despite symptom resolution 1, 2

The American Academy of Otolaryngology-Head and Neck Surgery recommends assessing the timing of onset, with sudden onset (seconds to minutes) strongly suggesting vascular etiology (stroke/TIA), while gradual progression over hours to days suggests other causes 1, 2, 3
The American Academy of Neurology suggests that the pattern of facial weakness, including upper and lower face involvement (central pattern), indicates stroke, while isolated lower face sparing forehead suggests peripheral seventh nerve pathology 1, 4, 3

The American Heart Association states that transient ischemic attack (TIA) or resolving stroke is the most dangerous diagnosis and must be excluded first, with sudden onset and central facial pattern (forehead spared) plus arm weakness 1, 2
The American Academy of Otolaryngology-Head and Neck Surgery recommends considering Bell's palsy when there is sudden onset of unilateral facial weakness affecting both upper and lower face, with no arm weakness, and forehead involved (peripheral pattern) 4, 3

The American Academy of Otolaryngology-Head and Neck Surgery suggests that oral corticosteroids (prednisone 1-1.5 mg/kg daily) improve recovery in Bell's palsy, once stroke is excluded 4
The American Heart Association recommends time-dependent interventions (thrombolysis, thrombectomy) if within treatment window, and admission for stroke workup and secondary prevention for stroke/TIA 2