The 76-year-old justice, who underwent surgery for pancreatic cancer in February,as a precautionary measure, according to the Supreme Court Press Office.
She had received an iron sucrose infusion at 4:50 p.m. to treat a deficiency that had been discovered in July.
About an hour later, she "developed lightheadedness and fatigue," the statement said. She was found to have a slightly low blood pressure, which the court said can occur after the type of treatment she received.
The July evaluation found "that she was in completely normal health with the exception of a low red blood cell count caused by deficiency of iron. Intravenous iron therapy was administered in a standard fashion," the court statement said.
Ginsburg underwent surgery for pancreatic cancer in February but returned to work quickly.
It's not uncommon for Justices, especially the older ones, to have ailments from time to time, said CBS News legal analyst Andrew Cohen. Most recently, the former Chief Justice William Rehnquist was able to perform his duties despite the fact that he was very sick, in many ways more ill than Ginsburg.
"She survived pancreatic cancer," Cohen said. "But clearly the treatments and side effects take their toll from time to time, especially for a 76-year-old woman. She's only the second female Justice and by all accounts a key part of the Court's inner dynamic."
Two months after her surgery, Ginsburg told law students at a symposium at Ohio State University that serving on the Supreme Court was "the best and the hardest job I've ever had." She said at the time that she wanted to match the tenure of Justice Louis Brandeis, who served for more than two decades and retired at age 82.
Nominated by President Bill Clinton, Ginsburg took her seat on the Supreme Court on Aug. 10, 1993. She had been a judge on the U.S. Court of Appeals for the District of Columbia Circuit since 1980.