Alternative medicine:

"When it came to the treatment of diseases, the ancient Romans had no shortage of magical remedies, several of which involved iron nails. To cure epilepsy, the first-century historian Pliny the Elder advised driving a nail into the ground at the spot where the afflicted person’s head lay at the start of the seizure. The Romans hammered nails into doors to avert plagues and pounded coffin nails into thresholds to keep nightmares at bay. Nails from tombs and crucifixions were sometimes even worn around the neck as talismans against fevers, malaria and evil spells."

https://www.nytimes.com/2023/03/25/science/archaeology-ancient-rome-tomb.html