King Charles was briefly hospitalized on Thursday due to “temporary” side effects from his ongoing cancer treatment, according to reports.

Despite the health scare, the 76-year-old monarch was discharged and returned to Clarence House by Thursday evening, The Sun reported. As a result, his scheduled events for Friday were canceled.

“Following scheduled and ongoing medical treatment for cancer this morning, The King experienced temporary side effects that required a short period of observation in hospital,” a Buckingham Palace spokesman stated.

“His Majesty has now returned to Clarence House and as a precautionary measure, acting on medical advice, tomorrow’s diary programme will also be rescheduled.”

Back at home, the king was reportedly in good health and carrying on with his royal duties.

According to The Sun, he was driven to the hospital in a regular car rather than an emergency vehicle, and Queen Camilla did not accompany him on the trip.

Charles had surgery for an enlarged prostate last year and later disclosed his cancer diagnosis in February.