At least 24 people have died and thousands injured in clashes between protesters and police.
Demonstrators in Chile gathered in public squares on Thursday for another round of protests that started over a hike in public transport fares but have broadened to encompass grievances over low wages, the high cost of living and social inequality.
In the capital Santiago, the protest started in the Italia Square - renamed "Dignity Square" - and the Avenue Libertador General Bernardo O'Higgins, better known as Alameda.
Anti-riot police used tear gas, rubber bullets and water cannons against protesters.
The protests also took place in the cities of Temuco, where thousands of people took to the streets, as well as Concepcion, where people also paid tribute to the anniversary of a young indigenous man who was shot dead by police in circumstances that are still under investigation.
The father of Camilo Catrillanca, a Mapuche man from the southern Araucania region, which has long been in conflict with the state, appealed to people to demonstrate "calmly."
On Thursday, the health ministry announced an alert across six of Chile's 16 regions to release extra funding amid a surge of 10,000 trauma cases and an unspecified increase in people seeking treatment for mental health issues.
The ministry did not link the health issues to the protests, but said they were due to "a situation of high health risk to the population".
The police have been heavily criticized for their handling of the demonstrations, with medical experts saying that more than 200 protesters have suffered eye injuries or been blinded by tear gas canisters and rubber bullets. This week, the police chief said he would fit firearms officers with surveillance cameras and deploy more human rights experts.
Ana Piquer, the executive director of Amnesty International Chile, said Pinera should respond to the many complaints of police excesses.
"We don't want to see any more victims of police violence anywhere in Chile, killed or seriously injured simply for raising their voice on social demands," she said.
Kattya Barrera, 19, of Santiago's low-income La Florida neighborhood said she believed nothing had changed since Catrillanca's death. "When someone goes out to demonstrate, they take out their eyes," she said. "Today isn't just about Catrillanca, it's for everyone."