There are many advantages to using INNs when thinking about, talking about and prescribing drugs: greater understanding of drugs, lower risk of confusion, and freedom from the influence of pharmaceutical companies.
 

There are many advantages to using INNs when thinking about, talking about and prescribing drugs: greater understanding of drugs, lower risk of confusion, and freedom from the influence of pharmaceutical companies' marketing strategies.
 
In practice, INNs convey information about the therapeutic class to which drugs belong, and make it easier to teach health professionals about drugs and to identify redundant prescriptions. The use of INNs also reduces the risk of confusion between drugs, informs patients about the true nature of their treatments, and frees healthcare professionals and patients from the influence of pharmaceutical advertising.

Obstacles are few and easily overcome
There are very few situations in which INN-only prescribing is inappropriate. They mainly involve drugs with a narrow therapeutic index, certain pharmaceutical forms, or certain clinical situations in which it is better to stick to a single product throughout treatment (either the originator drug or a generic version) and to avoid substitution.
INN-based prescribing does not necessarily mean prescribing a generic and, in contrast to popular belief, drugs prescribed by their INN are reimbursable  in many countries.

Seven tips to improve INN-based prescribing
Here are a few procedures and tricks that healthcare professionals can put in place to help them use INNs every day for every prescription:

1. Compile and classify a list of the drugs you prescribe or recommend, using their INNs, and advise students to do likewise;
2. Choose prescribing software in which drugs are entered directly using INNs rather than brand names;
3. Select treatment guidelines produced independently of the pharmaceutical industry, that list drugs by their INN, such as the British National Formulary (BNF);
4. Use the INN leaflets produced by the Medicines in Europe Forum to educate and inform patients and colleagues ;
5. If you are unfamiliar with INNs or worried about confusing patients if you switch to INN-prescribing too quickly, practise initially by adding the INN before the brand name on all your prescriptions;
6. In addition to the INN, include as much information as necessary about the drug on the prescription: route of administration, pharmaceutical form, dose strength, pack size, flavouring, dosing device (for example for an inhaled drug), etc.;
7. For a few types of drug, include the brand name next to the INN: drugs with a narrow therapeutic index, or when it is better that the same product (the originator drug or a specific generic version) is dispensed each time.
    

©Prescrire November 2014

For more information:

"Ordonnance : la dénomination commune internationale (DCI) au quotidien" Rev Prescrire 2012 ; 32 (346) : 586-591. (pdf in French, free)

"Think INN, prescribe INN, dispense INN" Prescrire International 2000; 9 (50): 184-190. (pdf, subscribers only)