Three athletes were stripped of medals after failing doping tests, the International Paralympic Committee announced on Sunday. Slovakian pilot cyclist Juraj Petrovic lost his silver medal and powerlifters Cheikh Younes of Syria and Ali Hosseini of Iran have to return their bronzes.
Younes and Hosseini, along with another powerlifter, Estonian Aleksandr Koroljov, also received two-year bans.
The latest violations take the Games total of doping cases to seven.
The IPC have so far carried out 529 of the 670 doping tests scheduled at the Paralympics.
Petrovic, who won silver with visually-impaired rider Vladislav Janovjak, tested positive for adverse amounts of a glucocorticosteroid called methylprednisolone.
Younes and Hosseini tested positive for anabolic agents, while Koroljov was penalised for taking a banned diuretic agent.