Practices should maintain a ‘carers register’, according to the Royal College of General Practitioners.
The body representing the UK's GPs has called for regulary check-ups on the mental wellbeing of carers.
RCGP said carers tend to “neglect their own needs”, claiming around 40% experience depression or psychological problems.
Holding routine appointments and maintaining a carers' register within GP practices could solve the "hidden" problem and protect the £119 billion carers save the taxpayer, the RCGP added.
“In many cases it is only a matter of time before [carers] themselves become ill,” claimed RCGP chair Dr Clare Gerada.
She said: "They are at risk physically and emotionally with stress-related illnesses but it can be hard for them to admit that they are struggling."
Dr Gerada told the BBC: "Unfortunately at the moment as with the rest of the health service, GPs are heaving under the workload and what this report is saying is that we have to target resources where they are most needed and they are most needed with carers.
"There are serious problems going on at the moment across the whole of the NHS but in particular in general practice, but what we mustn't do is forget the hidden group of those that need most care which carers are most certainly part of."
The RCGP has drawn up a checklist as part of new online guidance which also includes appointing a carers' champion in all GP surgeries, and carrying out audits to measure improvements in carer support.