Bangkok, Sep 3 (IANS): Thailand's King Bhumibol Adulyadej was undergoing treatment at a hospital in Bangkok after suffering a "severe infection", the Royal Palace said on Saturday.
King Bhumibol had breathing difficulties and was treated with antibiotics, CNN reported.
Shortly after, his blood pressure came down and he developed a fever.
Tests showed he had reduced kidney function and fluid in his lung, according to the Royal Palace statement.
His condition improved on Friday, but he remains hospitalised for monitoring, CNN reported citing the statement.
The 88-year-old king has been in and out of hospital in recent months. Last year, he was discharged after surgery to remove his gallbladder, the palace said at the time.