Zimbabwe's main nurses' union urged the government to negotiate and warned that lives would be lost if the dispute was not resolved quickly.
The government and health workers are at an impasse after inflation jumped to 131.7 percent in May, a grim echo of the hyperinflation that wiped out people's savings a decade ago.
Government workers rejected the below-inflation 100 percent wage hike offer on Friday.
At Sally Mugabe Hospital in Harare, patients seeking treatment sat in the courtyard while doctors, nurses, radiographers and pharmacists left their workplaces to protest.
"The salaries that the health workers received last week were pathetic," Enock Dongo, head of the Zimbabwe Nurses' Association, told Reuters, adding that the majority were paid 20,000 Zimbabwe dollars ($53) a month.
He said health professionals across the country had decided to strike until they were paid US$540 a month, the pay they used to receive in 2018 before the local currency slumped.
A government spokesperson did not immediately respond to a request for comment.
President Emmerson Mnangagwa, who took over from longtime leader Robert Mugabe in a 2017 coup, has struggled to end an economic crisis that started under his predecessor.