Generic Prescribing

Synonym: non-proprietary prescribing.

The term "generic prescribing" describes the use in prescribing of a non-proprietary title for a pharmaceutical preparation. The non-proprietary titles in the British National Formulary (BNF) are often titles from the European Pharmacopoeia, British Pharmacopoeia or British Pharmaceutical Codex 1973. In this way we know that the preparations prescribed by non-proprietary title must comply with the standard of the particular publication as required by Section 65 of the Medicines Act.

In March 2004 it was announced by the Chief Medical Officer that the names of medicines would be simplified with the aim of reducing the risk of error in the prescribing and dispensing of medicines.¹ The simplification referred to the change from the 'British Approved Names' (BANs) to the international system of 'recommended International Non-Proprietary Names' (rINNs). For example bendrofluazide (BAN) becomes bendroflumethiazide (rINN). A full list of names affected can be found on the Medicines and Healthcare products Regulatory Agency (MHRA) website.² Some software systems have taken more than 2 years to adopt the new nomenclature.

Generic prescribing allows for any suitable drug, rather than a particular brand of drug, to be dispensed. This can lead to cost savings because cheaper alternatives can be prescribed. It may avoid delay because the chemist can dispense a wider range of alternative preparations, rather than being limited to one which may not be stocked. Many practices may achieve 80% generic prescribing but a higher rate is not thought to be advantageous and may carry risks. Primary care trusts (PCTs) have used prescribing incentive schemes to improve the quality and cost of prescribing.^3,4,5 The most frequently monitored prescribing indicator was generic prescribing used by 88% of PCTs. However, specific advice is needed to maintain quality and make financial savings. Recently the National Audit Office published a report indicating that primary care trusts could save up to £200 million by encouraging all PCTs to prescribe as efficiently as the top performing 25%.⁶ The specific improvements relating to generic prescribing were:

• Generic prescribing of simvastatin
• Generic prescribing of proton pump inhibitors

It is widely appreciated that rates of generic prescribing need careful interpretation when passing judgement on the quality of prescribing.

Broadly speaking brand names or proprietary titles should be used where it is clear that prescribing generically will create problems with bioavailability or lead to confusion for the dispensing chemist or the patient. It is not always possible to prescribe generically because a non-proprietary title does not always exist.
Examples are:

• Where there is a particularly narrow therapeutic index. For example:
  • Lithium carbonate
  • Ciclosporin
• With modified release preparations such as:
  • Theophylline
  • Diltiazem
  • Isosorbide mononitrate
  • Nifedipine
• With compound preparations, for example:
  • Oilatum emollient
• With certain combined preparations, for example:
  • Hormone replacement therapy
  • Oral contraceptives
• When the same drug is used for different and separately branded indications, for example:
  • Cabergoline used as Dostinex®, (500 microgram preparation) for Parkinson's Disease and hyperprolactinaemia and as Cabaser®, (1 mg and 4 mg) for Parkinson's Disease.
• When the same drug is formulated to give different potency, for example:
  • Qvar®, CFC free inhalers. A 100 microgram dose of Qvar is equivalent in potency to 200-250 micrograms of beclometasone by CFC-containing inhaler.

• Generic prescribing rates are much higher in the UK than many other countries. Efforts in other countries are being made to increase rates of generic prescribing often as part of efforts to improve the quality and efficacy of prescribing.^7,8,9
• Patients' concerns about generic prescriptions are very common and often centre on the perception that cheaper drugs may be inferior.¹⁰ One study from France, however, reported lower levels of acceptance of generic prescribing amongst general practitioners when compared with pharmacists and the general public.¹¹ A study amongst French ophthalmologists showed an acceptance of the equivalence of generic prescriptions for glaucoma but this did not translate into the issuing of such a prescription because of lack of concern over cost.¹²
• Confusion over brand names is also an issue and education by prescribing doctors, dispensing pharmacists and manufacturers is important.¹³
• The scope for cost saving is greatest in countries with low rates of generic prescribing.⁸ In the UK the scope for big cost savings is correspondingly much smaller. Incentives to prescribing physicians are suggested in countries with low rates of generic prescribing and have certainly been used in the UK.⁸
• Concerns over the therapeutic equivalence of branded products and generics are common amongst physicians too.¹⁴ This is true in areas of prescribing where equivalence is critical such as with anticonvulsants and anticoagulants.^14,15,16
• A recent study concluded that cheaper generic statins were as effective at achieving QOF targets as more expensive alternatives.¹⁷
• More savings might be made with generic prescribing with improved management of the purchasing of generic drugs by the NHS.¹⁸

This can be achieved by:

• Education of doctors and pharmacists
• Education and information for patients
• Good quality control and regulation to maintain therapeutic equivalence*
• Incentives to encourage generic prescribing
• Careful selection of brand names

*The Medicines and Healthcare products Regulatory Agency (MHRA) was formed in April 2003 from the merger of the Medicines Control Agency (MCA) and the Medical Devices Agency (MDA).
It has regulatory duties and supervises production of the British Pharmacopoeia. When patents expire on drugs then generic drugs can be produced according to standards regulated by the MHRA.