A gentleman aged 70 years comes into the pharmacy with his daughter. She is assisting him as he walks. His is also having difficulty speaking, and his hand is shaky as he hands you the refill information. He requests an early refill of his pain medication, gabapentin, which the insurance declines. You remember seeing him 2 weeks ago, and he was completely independent.

Mystery: What has happened to him? He seems to have had a stroke or developed some sort of altered mental status.

Solution: He is having adverse effects from taking too much gabapentin.