The controversial plan bans expatriates from seeking medical help in the morning unless in an emergency, while giving Kuwaitis priority.
Staff also are segregated according to their nationality, with Kuwaitis working in the morning and expat doctors in the afternoon.
The move is seen as favourable to Kuwaitis while reducing the level of care given to expats, who make up about two-thirds of the Gulf state’s population but would have fewer hours they could seek medical attention.
MPs approved the idea in March and a trial began at Jahra Hospital, in Kuwait City’s west, in June.
It was supposed to be for six months before a decision was made on a wider implementation but Kuwait Times reported on Monday the Health Ministry had determined the trial was successful and split hours would be rolled out across the country.
Human Path Organisation secretary Taher Al-Baghly said in February the segregation was discriminatory.
“The health service will not be equal, because consultants work in the morning and this will lead to variations in service levels,” he said.