The Colombian writer Gabriel Garcia Marquez, winner of the 1982 Nobel Prize for Literature, has been taken to hospital in Mexico City.
Garcia Marquez, who is 87, is being treated for a lung and urinary tract infection, said Mexican officials.
He has made few public appearances in recent years.
He is considered one of the greatest Spanish-language authors of all time, best known for his masterpiece of magic realism, A Hundred Years of Solitude.
The 1967 novel has sold more than 30 million copies around the world.
Garcia Marquez, who has lived in Mexico for more than 30 years, was admitted on Monday night to a hospital in Mexico City, the National Nutrition Institute Salvador Zubiran.
"The patient has responded to treatment. Once he has completed his course of antibiotics his discharge from the hospital will be evaluated,'' Mexico's Secretary of Health said in a statement.
Two years ago, his younger brother admitted publicly for the first time that Garcia Marquez was suffering from dementia and had stopped writing.
Jaime Garcia Marquez said that Gabo, as the author is affectionately known, often phoned to ask basic questions.
"He is doing well physically, but he has been suffering from dementia for a long time," he said. "Sometimes I cry because I feel like I'm losing him."
Gabriel Garcia Marquez's other novels include Love in the Time of Cholera, Chronicle of a Death Foretold and the The General in His Labyrinth.