Emergency department clinicians with limited resources are relied upon to deliver safe and timely patient care. Clinicians rely on cognitive biases such as anchoring, availability, and premature closure based on experience and quick mental algorithms to streamline medical data and arrive at a diagnosis. Although this is a time-saving and efficient method in the management of uncomplicated illnesses, it can result in a wrong diagnosis when managing patients with complicated presentations such as a stroke or a stroke mimic. Two conditions that present similarly, making it difficult to differentiate between them, are Todd's paralysis (a stroke mimic seen in selected patients with epilepsy) and acute ischemic stroke. However, by clinical reasoning, clinicians can formulate an accurate diagnosis while avoiding diagnostic biases. Incorporating clinical reasoning into the diagnostic process consists of gathering pertinent data, performing a diagnostic time-out, and arriving at a diagnosis reflective of data findings.