The call for clearly-defined medical practices follows an inquiry into the death of Leon Patterson, who was found naked in police custody.
An inquest jury in November returned a verdict of "misadventure to which neglect contributed". Mr Patterson, 31, from north London, was arrested in Stockport, Greater Manchester, on suspicion of stealing. Six days after his arrest he was taken to Stockport Magistrates' Court, where he spent eight hours lying naked and handcuffed on a stone floor before being transferred to a holding cell at Denton police station where he was later found dead. There was clear evidence that he had not taken adequate fluids and that he had been vomiting and had diarrhoea.
There cause of death was considered to have been a "complex metabolic disorder" resulting from drug withdrawal symptoms and gastroenteritis.
Molly Meacher, a member of the PCA, said that in view of the increasing numbers of people coming into police custody suffering from psychiatric disorders or drug addiction, police forces need to consider whether drug and psychiatric experts should be available. The police doctors should also clearly say how a sick prisoner should be treated.