Dozens of inmates at the Iowa State Penitentiary were given doses of the Pfizer coronavirus vaccine far in excess of what is recommended. Paolo Lo Debole/Getty Images Dozens of inmates received overdoses of Pfizer's coronavirus vaccine, the Iowa Department of Corrections said Wednesday. One prisoner's mother said doctors told her that her son received "six times the recommended amount," the Des Moines Register reported. Officials said the inmates are being "closely monitored." See more stories on Insider's business page. Officials at a maximum-security prison in Iowa gave 77 inmates doses of the Pfizer coronavirus vaccine that were several times more potent than recommended, the Des Moines Register reported.The incident, which occurred Tuesday, took place at the Iowa State Penitentiary in Fort Madison.The mother of one inmate told the Register her son received a dose that was "six times the recommended amount," according to doctors."The affected inmates have been notified and are being closely monitored by medical staff.