A Sydney doctor has suffered serious injuries after allegedly being stabbed by a patient.

Police were called to a medical practice on Pitt St in the city’s CBD last Friday, where they found the 85-year-old doctor had a stab wound to his neck.

He was treated by emergency services at the scene before being transferred to hospital in a stable condition.

A 57-year-old man was subsequently arrested at the scene and taken firstly to Surry Hills Police Station, before also being taken to hospital, where is currently under police guard.

The man is believed to have been a patient of the doctor, and was being treated when the alleged stabbing occurred.

The 57-year-old man was charged the next day with wounding a person with intent to cause grievous bodily harm.

Police confirmed they are also investigating the circumstances surrounding the alleged stabbing.

He was refused bail to appear before Parramatta Local Court on Sunday, and was again refused bail to appear before Downing Centre Local Court on November 27.