Q&A 247.3
Which medicines should be considered for brand-name prescribing in primary care?
Prepared by UK Medicines Information (UKMi) pharmacists for NHS healthcare professionals
Before using this Q&A, read the disclaimer at
Date prepared: July 2013 (partial update December 2013)
Summary
Prescribing medicines by generic rather than brand name can improve cost-effectiveness and is encouraged. However, there are some circumstances in which continuity of the same brand is important for patient safety and brand-name prescribing preferred.These include:
Where there is a difference in bioavailability between brands of the same medicine, particularly if the medicine has a narrow therapeutic index.
Where modified release preparations are not interchangeable.
Where products contain multiple ingredients and brand name prescribing aids identification.
Where there are important differences in formulation between brands of the same medicine.
Where administration devices (e.g. inhaler or self-injection) have different instructions for use and patient familiarity with one product is important.
Where the product is a biological rather than chemical entity.
Background
Medicines may be prescribed by ‘brand’ (proprietary) or ‘generic’ (recommended International Non-proprietary Name, rINN) name.
In primary care, if a medicine is prescribed by brand name, the pharmacist may dispense only the specified brand and is reimbursed for doing so. If a medicine is prescribed by generic name, the pharmacist may dispense any suitable generic or branded product and is reimbursed at a set price, listed in the Drug Tariff. Proposals for ‘generic substitution’ whereby community pharmacists would be allowed to supply a generic preparation even if a branded product were prescribed have been rejected in England [1].Legislation has recently been passed allowing generic substitution in Ireland for medicines on an ‘interchangeable list’ maintained by the Irish Medicines Board [2].
Advantages of generic prescribing are that it is generally more cost-effective than prescribing by brand name and, because it allows any suitable product to be dispensed, can reduce delays in supplying medicines to the patient [3,4]. Increasing the level of generic prescribingin the UK has long been encouraged. A measure of generic prescribing in primary care (‘potential generic savings’) in England is reported as a prescribing comparator [5].
Although generic prescribing is encouraged there are some circumstances in which it is preferable to prescribe by brand name.Broadly these circumstances are where continuity of the same brand is important due to differences in bioavailability, where patient training differs between products and to aid identification where products have multiple ingredients. The NHS Dictionary of Medicines and Devices (dm+d) and NHS Prescription Service Common Drug Reference database annotate medicines not recommended for generic prescribing [6, 7]. Prescribing software systems may also indicate medicines for which brand name prescribing is preferred. Specific circumstances are described below:
Where there is a difference in bioavailability between brands of the same medicine, particularly if the medicine has a narrow therapeutic index. In these circumstances, lack of clarity over which preparation is intended when prescribing can lead to the patient receiving a sub-therapeutic or toxic dose. Examples include ciclosporin, lithium, CFC-free beclometasone metered dose inhalers and some antiepileptic medicines.
Where modified release preparations are not interchangeable, particularly if the medicine has a narrow therapeutic index. This avoids confusion between formulations with different release characteristics. Examples include aminophylline, diltiazem and morphine.
Where there are important differences in formulation between brands of the same medicine. For example, fentanyl patches are available as matrix formulations and reservoir formulations. Reservoir patches must not be cut because damage to the rate-limiting membrane can lead to a rapid release of fentanyl resulting in overdose. If the prescriber intends the patch to be cut (although this is unlicensed and not recommended by the MHRA) then the prescription must specify a brand of matrix formulation patch.
Where products contain more than one ingredient and brand name prescribing aids identification. This is useful when prescribing products with multiple ingredients (e.g. pancreatin supplements, skin and scalp preparations) and to differentiate between similar products where patient familiarity with a brand is important (e.g. hormone replacement therapy and oral contraceptives).
Where administration devices have different instructions for use and patient familiarity with one product is important. For example salbutamol dry powder inhalers and adrenaline pre-filled syringes.
Where the product is a biological rather than chemical entity. Such agents are licensed as ‘biosimilar’ medicines. Examples include erythropoietin and somatropin (growth hormone) preparations.
Answer
The following table lists medicines that might be considered for brand-name prescribing.This table has been compiled using a number of sources. Specific references for individual medicines are included where appropriate.
BNF / Drug or drug class / Reason for consideringbrand-name prescribing / Specific referencesChapter 1
1.1.1 / Antacids preparations containing simeticone / To aid identification. Products contain multiple ingredients. / BNF
1.1.2 / Compound alginates and proprietary indigestion preparations / To aid identification. Products contain multiple ingredients. / BNF
1.5.1 / Mesalazine oral preparations / The delivery characteristics of oral mesalazine preparations may vary and should not be considered interchangeable. / BNF
1.6.1 / Bulk forming laxatives / To aid identification. Products contain multiple ingredients. / -
1.6.4 / Macrogols (polyethylene glycols) / To aid identification. Products contain multiple ingredients. / -
1.7.2 / Compound haemorrhoid preparations / To aid identification. Products contain multiple ingredients. / -
1.9.4 / Pancreatin supplements / To aid identification. Products contain multiple ingredients. / -
Chapter 2
2.6.2 / Diltiazem modified release (MR) preparations / MR preparations have different release characteristics and are not interchangeable. / BNF
dm+d
2.6.2 / Nifedipine modified release preparations / MR preparations have different release characteristics and are not interchangeable. / BNF
dm+d
Chapter 3
3.1.1 / Formoterol dry powder inhalers / Patient familiarity with one brand is important; instructions for use vary between preparations. / dm+d
3.1.1 / Salbutamol dry powder inhalers / Patient familiarity with one brand is important; instructions for use vary between preparations. / dm+d
3.1.3 / Theophylline modified release preparations / MR preparations have different release characteristics and are not interchangeable. Theophylline has a narrow therapeutic index. / BNF
3.1.3 / Aminophylline modified release preparations / MR preparations have different release characteristics and are not interchangeable. Aminophyline has a narrow therapeutic index. / BNF
dm+d
3.2 / Beclometasone dipropionate CFC-free pressurised metered dose inhalers / Qvar and Clenil Modulite are not interchangeable. Qvar has extra-fine particles and is approximately twice as potent as Clenil Modulite and CFC-containing beclometasone inhalers. The MHRA has advised that CFC-free beclometasone inhalers should be prescribed by brand name. This applies also to combination products. / BNF
dm+d
MHRA[8]
3.2 / Beclometasone dry powder inhalers / Patient familiarity with one brand is important; instructions for use vary between preparations. / dm+d
3.2 / Beclometasone and formoterol CFC-free metered dose inhalers / See beclometasone CFC-free metered dose inhalers, above. / BNF
MHRA[8]
3.2 / Budesonide dry powder inhalers / Patient familiarity with one brand is important; instructions for use vary between preparations. / -
3.4.3 / Adrenaline (epinephrine) pre-filled syringes / Patient familiarity with one brand is important; instructions for use vary between preparations. / BNF
dm+d
Chapter 4
4.2.3 / Lithium preparations / Preparations vary widely in bioavailability. Changing the preparation requires the same precautions as initiation of treatment. Lithium has a narrow therapeutic index. / BNF
dm+d
4.4 / Methylphenidate modified release preparations / MR preparations contain different proportions of immediate-release and modified-release methylphenidate. / BNF
dm+d
4.7.2 / Morphine oral modified release preparations / MR preparations have different release characteristics; Patient familiarity with one brand is important. / PCF4 [9]
4.7.2 / Fentanyl patches / Patches are available as matrix and reservoir formulations; Patient familiarity with one brand is important. Reservoir patchesmust not be cut because damage to the rate-limiting membrane can lead to a rapid release of fentanyl resulting in overdose. If the prescriber intends the patch to be cut (NB: unlicensed and not recommended by the MHRA) then the prescription must specify a brand of matrix formulation patch. / PCF4 [9]
4.7.4 / Botulinum toxin type A / Preparations are not interchangeable due to differences in potency. / BNF
dm+d
4.8.1 / Antiepileptic drugs / The MHRA has classified antiepileptic drugs (AEDs) into three categories of risk, based primarily on their therapeutic index and physiochemical characteristics (in particular solubility and permeability across membranes) indicative of potential differences between formulations.
Category 1:
Specific measures are necessary to ensure consistent supply of a particular product (which could be either a branded product or a specified manufacturer’s generic product).
Category 2:
NB: By default, this category includes all AEDs not listed in categories 1 or 3.
The need for continued supply of a particular manufacturer’s product should be based on clinical judgement and consultation with patient and/or carer.
Category 3:
No specific measures are normally required and these AEDs can be prescribed generically and without specifying a specific manufacturer’s product: / MRHA [10,11]
NICE recommends continuity of the same brand, or the same generic preparation, for patients with seizure disorders, unless the prescriber (in consultation with the patient and their family or carers) considers this not to be a concern.
(For individual antiepileptic agents, see below.) / NICE[12]
4.8.1 / Carbamazepine / MHRA Category 1 (see ‘Antiepileptic drugs’ above). / MRHA [11]
4.8.1 / Ethosuxamide / MHRA Category 3 (see ‘Antiepileptic drugs’ above). / MRHA [11]
4.8.1 / Gabapentin / MHRA Category 3 (see ‘Antiepileptic drugs’ above). / MRHA [11]
4.8.1 / Lacosamide / MHRA Category 3 (see ‘Antiepileptic drugs’ above). / MRHA [11]
4.8.1 / Levetiracetam / MHRA Category 3 (see ‘Antiepileptic drugs’ above). / MRHA [11]
4.8.1 / Phenobarbital / MHRA Category 1 (see ‘Antiepileptic drugs’ above). / MRHA [11]
4.8.1 / Phenytoin / MHRA Category 1 (see ‘Antiepileptic drugs’ above). / MRHA [11]
4.8.1 / Pregabalin / MHRA Category 3 (see ‘Antiepileptic drugs’ above). / MRHA [11]
4.8.1 / Primidone / MHRA Category 1 (see ‘Antiepileptic drugs’ above). / MRHA [11]
4.8.1 / Tiagabine / MHRA Category 3 (see ‘Antiepileptic drugs’ above). / MRHA [11]
4.8.1 / Vigabatrin / MHRA Category 3 (see ‘Antiepileptic drugs’ above). / MRHA [11]
4.9.1 / Apomorphine pre-filled syringe / Patient familiarity with one brand is important; instructions for use vary between preparations. / dm+d
4.9.3 / Botulinum toxin type A / Preparations are not interchangeable due to differences in potency. / BNF
dm+d
Chapter 6
6.1.1 / Insulins / Patient familiarity with the same brand is important; training is required in the use of specific devices for self-injection. / dm+d
6.4.1 / Hormone replacement therapy oral preparations / Different brands of the same formulation are available. Patient familiarity with one brand is important. / -
6.4.1 / Estradiol transdermal patches / Different brands of the same formulation are available. Patient familiarity with one brand is important. / -
6.5.1 / Somatropin injection cartridges / Patient familiarity with the same brand is important and training is required in the use of specific devices for self-injection. Some somatropin preparations are licensed as ‘biosimilar’ medicines. / BNF
dm+d
Chapter 7
7.3.1 / Combined oral contraceptives / Different brands of the same formulation are available. Patient familiarity with one brand is important. / -
7.3.2 / Progestogen only oral contraceptives / Different brands of the same formulation are available. Patient familiarity with one brand is important. / -
7.4.5 / Alprostadil injection / Patient familiarity with one brand is important; instructions for use vary between preparations. / dm+d
Chapter 8
8.2.1 / Azathioprine / Different formulations may vary in bioavailability; to avoid reduced effect or excessive side effects, it is important not to change formulation except on the advice of a transplant specialist. / BNF
Eur Soc Org Trans [12]
8.2.1 / Mycophenolate / Generic and branded preparations are considered bioequivalentbut it may be prudent not to change formulation except on the advice of a transplant specialist.
Mycophenolate mofetil and mycophenolic acid preparations are not interchangeable. / BNF
Eur Soc Org Trans [12]
PJ [13]
8.2.2 / Ciclosporin / Preparations are not interchangeable and should be prescribed by brand-name to avoid inadvertent switching.It is important not to change formulation except on the advice of a transplant specialist. Ciclosporin has a narrow therapeutic index. / BNF
dm+d
Eur Soc Org Trans [12]
MHRA [14]
8.2.2 / Tacrolimus / Preparations are not interchangeable; care should be taken to ensure the correct preparation is prescribed and dispensed.It is important not to change formulation except on the advice of a transplant specialist. Tacrolimus has a narrow therapeutic index. / BNF
dm+d
MHRA [15]
8.2.4 / Interferon pre-filled disposable injection devices
Peginterferon pre-filled disposable injection devices / Patient familiarity with one brand is important; instructions for use vary between preparations. / dm+d
Chapter 9
9.1.3 / Erythropoietins / Patient familiarity with the same brand is important and training is required in the use of specific devices for self-injection. Some epoetin preparations are licensed as ‘biosimilar’ medicines. / BNF
dm+d
9.1.6 / Granulocyte-colony stimulating factors / Patient familiarity with the same brand is important and training is required in the use of specific devices for self-injection.
Filgrastim preparations havebeen approved as ‘biosimilar’. / dm+d
BNF
9.2.1 / Oral rehydration salts / To aid identification. Products contain multiple ingredients. / -
9.5.1 / Calcium salts / To aid identification. Products contain multiple ingredients. / -
Chapter 12
12.3.5 / Saliva replacement products / To aid identification. Products contain multiple ingredients. / -
Chapter 13
13.1-13.10 / Preparations for skin and scalp conditions containing multiple ingredients / To aid identification. Products contain multiple ingredients. Also, potency of topical corticosteroid preparations is a result of the formulation as well as the corticosteroid. / -
Chapter 14
14.4 / Human papillomavirus vaccine / Cervarix (bivalent vaccine) and Gardasil (quadravalent vaccine) are not considered interchangeable. / BNF
Limitations
This list of medicines may not be comprehensive.
References
1.Department of Health. Press release: No plans to implement generic substitution of medicines. 14 October 2010. Accessed at 4/9/2013.
2.Irish Medicines Board. Generic and interchangeable medicines. Accessed at 4/9/2013.
3.Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press. Accessed via 4/9/2013.
4.NHS Choices. Medicines information – brand names and generics. Reviewed 24/10/2012. Accessed at 3/9/2013.
5.NHSBusiness Services Authority. Prescribing comparators. Accessed at on 4/9/2013.
6.NHS Business ServicesAuthority. NHS Dictionary of Medicines and Devices (dm+d) Editorial Policy. Release 2.3. August 2013. Accessed via 4/9/2013.
7.Information Services, NHS Business Services Authority Prescription Services. Items indicated as not being suitable for generic prescribing, from the NHS Prescription Service Common Drug Reference database. Personal communication on 2/7/2013 (data produced 25/6/2013).
8.Medicines and Healthcareproducts Regulatory Agency. Inhaled products that contain corticosteroids. Drug Safety Update 2008; 12(1):8. Accessed at on 4/9/2013.
9.Twycross R, Wilcock A (eds). Palliative Care Formulary. 4th Edition. Nottingham:Palliativedrugs.com Ltd: 2011 pp362, 392.
10.Medicines and Healthcare products Regulatory Agency. Antiepileptic drugs: new advice on switching between different manufacturers’ products for a particular drug. Drug Safety Update November 2013; 7 (4): A1.Accessed at: 3/12/2013.
11.Medicines and Healthcare products Regulatory Agency. Formulation switching of antiepileptic drugs: A report on the recommendations of the Commission on Human Medicines from July 2013. Accessed at on 3/12/2013.
12.National Institute for Health and Clinical Excellence. Clinical guideline 137: The epilepsies – the diagnosis and management of the epilepsies in adults and children in primary and secondary care. January 2012. Accessed at on 4/9/2013.
13.European Society for Organ Transplantation Advisory Committee. Generic substitution of immunosuppressive drugs. Transpl Int 2011; 24(12): 1135-1141. Accessed at on 4/9/2013.
14.Tynan S and Jerram P. Generic or branded mycophenolate – what strategy should the NHS adopt? Pharm J 2010; 285 (7630): 659-660.
15.Medicines and Healthcare products Regulatory Agency. Ciclosporin must be prescribed and dispensed by brand name. Drug Safety Update Dec 2009; 3 (5): 2. Accessed at on 4/9/2013
16.Medicines and Healthcare productsRegulatory Agency. Oral tacrolimus products: prescribe and dispense by brand name only, to minimise the risk of inadvertent switching between products, which has been associated with reports of toxicity and graft rejection. Drug Safety Update 2012; 5(11): A1. Accessed at 4/9/2013.
Quality Assurance
Prepared by
Karoline Brennan, North West Medicines Information Centre
Date Prepared
February 2009 (partial revision May 2011)
Update prepared September 2013 (partial update December 2013)
Checked by
Simone Henderson, North West Medicines Information Centre
Christine Proudlove, North West Medicines Information Centre
Date of check
February 2009 (partial revision May 2011)
Update checked September 2013 (partial update December 2013)
Search strategy
In-house enquiries [Search terms: “generic prescribing”, “therapeutic equivalency”]
BNF online [Search terms: “brand”, “bioavailability”, “interchangeable”]
NICE Evidence Search [Search terms: generic prescribing, individual drug names]
NHS Choices [generic medicines]
Irish Medicines Board
BNF 65 paper copy
NHSBusiness Services Authority
General internet searches [Search terms included nhs generic medicines, QIPP generic prescribing, NHS England generic medicines]
Available throughNICE Evidence Search at