[WP] A new drug is developed that gives its users an unparalleled euphoria never before known to mankind. However, the drug has a peculiarity: it will kill the user within a week of dosing, except if the user is either younger than twelve or older than eighty.

In a moment his entire basement had melted into an entirely different world, and slowly, so very slowly, this world began to construct itself around him. And it started with blue. Light baby blue that filled his vision entirely, and then that blue became the walls that surrounded him and was sitting.
He looked down. He was in a desk. And he was so small.
He looked up. He was in a classroom, filled with children. Posters were hung every where on those blue walls that made him feel so calm, and it seemed that he had lived this entire place before. He looked at the teacher and realized he had.
He was in first grade again, looking up at his favorite teacher from childhood, Ms. Dow. She was holding with her a golden retriever.
And he remembered this day. It was one of the first weeks of school and Ms. Dow had brought her dog to school. It was one of Thomas's earliest memories being played out in real time right before him.
"Would anyone like to come pet Lucy here?" she said, and Thomas felt his arm shoot up like a shoot. He hadn't been in control of it, but he still felt it happen.
"Well come on up here, Thomas," and Thomas felt himself shuffle out of his chair and move toward the front of the class. He hadn't been in control of a thing. Everything in this world had already happened, and Thomas was just along for the ride. 
Yet still, he was feeling everything exactly the way he had felt it that day. He felt the eagerness to pet a dog. His parents had never let him have a dog, and he always wanted one so desperately bad. And this moment was so amazing to Thomas at the time, but he would have never remembered. He reached the front of the class and wrapped his arms around Lucy's ears and Tom looked into her eyes while she stayed back. He felt so happy. He felt that amazing sense of bliss and excitement exactly the way he had felt that day.
And suddenly, the room began to fade away and something a different world began constructing itself in it's place. He saw the blue sky, that blue calming sky. And then a ferris wheel and the smell of popcorn. He was walking on a board walk next to an ocean. He looked to his left and saw his Uncle Peter, a man who he hadn't seen or bothered to call in years. Uncle Peter looked at him with his amiable smile that might Thomas feel so calm. He remembered where he was now, he was off to the dock to spend the day fishing, something that had seemed like such a bore when suggested to him but ended up being one of the most relaxing days of his childhood.
So he went on with that memory. Spending the day fishing of the dock and washing the waves crash into the shore. He felt every emotion exactly how he felt them that day, an overwhelming feeling of peace and serenity, and after a while that memory deconstructed itself as well, and in it's place was Thomas's high school graduation, followed by the night he snuck out to go see his girlfriend and they spent the night laying on top of his car staring at the stars, followed by hundreds of more memories of happiness and bliss, some as small as the time when Thomas made a joke around his construction friends that they all got a good laugh out of.
It was incredible. All those painful memories were simply not there. Just all the positive memories in Thomas's life that he never considered to think back on. 
/r/WritingPrompts Thread