Greater care is needed in the prescription of generic over branded medicines, according to the Académie Nationale de Médecine.

It's a topic that is a hugely sensitive one in France, for over the past decade the use of generic medicines has been doggedly promoted by the French government as a means of reducing health service costs.

Although generic drugs can only be manufactured and sold once the patent on the branded drug has expired they are around one-third cheaper than branded originals so represent a considerable saving when their use is sanctioned.

Within the past few years push finally came to shove, with many hundreds of branded medicines being delisted by the government as no longer reimbursable due to equivalent generic medicines being available.

As a result, between 2000 and 2009 the use of generic medicines increased from 5.4% to 22.6% of the total market.

So, by pouring cold water on the idea that generic medicines are necessarily as effective or as appropriate as the original the physicians do threaten to undermine a key element of government health policy.

Although the report risks causing a major row, the Académie casts only a limited degree of circumspection on the use of generic medicines, which they consider should be used with 'prudence'.

They argue that even though generics may contain the same active ingredients, none is an exact copy of the original.

Generic medicines also contain different ‘inactive ingredients’ (used to formulate the active ingredient), which the physicians consider may have adverse side-effects on patients.

These inactive ingredients are called ‘excipients’, and different manufacturers do not always use the same ones when formulating their product.

As a result, some generic medicines may well be less effective, or they may take longer to take effect.

There may be undesirable psychological effects on a patient prescribed a generic medicine when they had become accustomed to a particular brand.

The authors of the report are also concerned about the lack of controls over the manufacture of the generics, many of which are produced in China or Asia.

Evidence of the growing lack of confidence in some generic medicines does seem to be shown by the practices adopted by doctors and their patients. Some doctors routinely insert on the prescription that the medicine they have prescribed is ‘Non Substituable (NS)’ by the chemist.

Last year there was also a reduction of 3% in the use of generic medicines over the brands (down from 630 million in 2010 to 614 million), although whether at the behest of doctor or patient remains unclear.

It is always possible for a patient to insist on the branded medicine, but if they do so they may well find that they have to pay for it out of their own pocket.