Surgeries in supermarkets? Sounds like trouble in store, if you ask me. This week a supermarket in Greater Manchester has dusted down one of its broom cupboards and has installed a GP consulting room.

Shoppers at Sainsbury’s in Heaton Park will be able to see a GP two evenings a week between 6.30pm and 9.30pm, and at lunchtimes on Saturdays.

A GP poised by the checkouts when your surgery is closed might seem like a brilliant idea. Who better to cast an expert eye over your grocery purchases and advise about the trans-fat content of that frozen lasagne or the nutritional value of the half-price satsumas with a short sell-by date? Well, seeing as you ask, a dietitian, but they don’t work nights and weekends.

However, a GP would be ideally placed to trip you up on your way to the fag counter and to divert your attention from the high-fat impulse-buy snack foods on offer by the tills. He could even tick the boxes labelled: “Encouraged to stop smoking” and “Dietary advice given” on your computer file and earn valuable reward points for himself.

If a pilot scheme was rolled out in my local Sainsbury’s, I’d offer 500 Nectar points for any patient who can get a course of antibiotics out of me without good reason and a “Five symptoms or less” queue for those in a hurry.

But don’t imagine that the instore doctors will be providing an instant service. Appointments have to be booked in advance via the patients’ usual GP surgeries.

So if you experience a searing pain up the coffee aisle or develop an uncomfortable swelling down by the bagged nuts while you’re shopping, then you’ll still have to rely on the emergency services if you can’t make it over to the local NHS walk-in centre.

You will have figured out by now that I’m far from convinced that this pilot will do anything useful. It will put doctors who don’t know the patients into rooms with patients who don’t know the doctors. Fine if you've broken an arm; not so good if you want your long-term rheumatoid arthritis medication reviewed.

This is a set-up designed to appeal to the kind of people who, as a rule, don’t often need to use our services. When asked in a recent survey, a quarter of them said that they didn’t think it was important to see the same doctor each time they went to the surgery.

But if you ask people with complicated medical problems, those who need to see their GP several times a year, then you get a very different answer.

I’ve been working in the same place for so long that the locals think of me as their doctor and, reciprocally, I think of them as my patients. Patronising and old-fashioned it may be, but this means that on the drive home from evening surgery I’m mulling over their problems and reminding myself to check whether a test result I’ve been waiting for has arrived in the post next morning. I doubt your supermarket GP will be doing the same.

So you might need to take a couple of hours off work once or twice a year to have your cardiovascular disease, asthma or diabetes monitored by a GP who knows you and your medical history. Get over it. You spend more time than that standing in queues at checkouts.

Dr Copperfield is a GP in Essex. He also writes for www.DoctorPortal.co.uk

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