"This is a huge breakthrough for access to birth control and a historic moment for women's health and equity," said Planned Parenthood president Cecile Richards in a statement. "The FDA's decision will make emergency contraception available on store shelves, just like condoms, and women of all ages will be able to get it quickly."
Nancy Northup, president and CEO of the Center for Reproductive Rights, also praised the decision.
Northup had previously argued that a minimum age limit and identification requirement for purchasing the drug over-the-counter amounted to "daunting and sometimes insurmountable hoops" for women to jump through.
Other organizations, however, have criticized the decision, warning that it may lead to an increase in promiscuity and sexually transmitted infections, as well as unsafe repeat use.
Opponents also argued that the new policy will undermine parents' rights to help make medical decisions for their children.
They warned that the pill is labeled as a cancer-causing carcinogen by the World Health Organization and is also associated with increased risk of blood clots, heart attacks, strokes and ectopic pregnancies. Furthermore, they said, there have not been studies on the effects of taking the drug during puberty.
"We're very concerned and disappointed at the same time because what we see here is the government caving to political pressure instead of putting first the health and safety of girls (and) parental rights," said Anna Higgins, director of the Family Research Council's Center for Human Dignity in a statement.
Pro-life organizations also noted the drug's potential to end an unborn human life.
Pushing unlimited abortion and contraception access "does not empower women, nor will it improve women's health in any way," said Father Shenan J. Boquet, president of Human Life International.
"By allowing very young girls to purchase powerful drugs like Plan B without parental notification or medical consultation this administration is showing a complete disregard for the health of young women, who may also end up unknowingly killing their unborn children."