Medicines Q&As
Q&A 247.1a
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 www.ukmi.nhs.uk/activities/medicinesQAs/default.asp
Date prepared: February 2009; partially revised May 2011
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 there are important differences in formulation between brands of the same medicine.
 Where products contain multiple ingredients and brand name prescribing aids identification.
 Where administration devices (e.g. inhaler or self-injection) have different instructions for use and
patient familiarity with the same 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 Nonproprietary 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. [1]
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. [2, 3, 4] Increasing the level of generic prescribing has been a long-term
Department of Health objective. A measure of generic prescribing in primary care (‘potential generic
savings’) is reported as a prescribing indicator. [3]
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) annotates medicines not recommended for generic prescribing; prescribing software
systems may also indicate medicines for which brand name prescribing is preferred. [5, 6] 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. For example ciclosporin, lithium, CFC-free beclometasone metered dose inhalers and some
antiepileptic medicines.
From the NHS Evidence website www.evidence.nhs.uk

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 which are available as matrix formulations (e.g. Durogesic DTrans,
Matrifen) and reservoir formulations (e.g. Tilofyl). 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 multiple ingredients 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 the
same 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 considering brand-name
prescribing
Specific
references
Chapter 1
1.1.2
Antacids preparations containing
simeticone
To aid identification. Products contain
multiple ingredients.
-
Compound alginates and
proprietary indigestion preparations
To aid identification. Products contain
multiple ingredients.
-
1.5.1
Mesalazine oral preparations
The delivery characteristics of oral
mesalazine preparations may vary and
should not be considered
interchangeable.
BNF
1.6.4
Macrogols (polyethylene glycols)
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
preparations
MR preparations have different release
characteristics and are not
interchangeable.
BNF
2.6.2
Nifedipine modified release
preparations
MR preparations have different release
characteristics and are not
interchangeable.
BNF
From the NHS Evidence website www.evidence.nhs.uk
BNF
Drug or drug class
Reason for considering brand-name
prescribing
Specific
references
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
3.2
Beclometasone dipropionate CFCfree 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 CFCcontaining beclometasone inhalers. The
MHRA has advised that CFC-free
beclometasone inhalers should be
prescribed by brand name. This applies
also to combination products.
BNF,
MHRA [7]
3.2
Beclometasone dry powder inhalers
Patient familiarity with one brand is
important; instructions for use vary
between preparations.
3.2
Beclometasone and formoterol
CFC-free metered dose inhalers
See beclometasone CFC-free metered
dose inhalers, above.
3.4.3
Adrenaline pre-filled syringes
Patient familiarity with one brand is
important; instructions for use vary
between preparations.
dm+d
BNF
dm+d
BNF,
MHRA [7]
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.
4.4
Methylphenidate modified release
preparations
MR preparations contain different
proportions of immediate-release and
modified-release methylphenidate.
4.7.2
Morphine oral modified release
preparations
MR preparations have different release
characteristics; Patient familiarity with one
brand is important.
From the NHS Evidence website www.evidence.nhs.uk
-
PCF3 [8]
BNF
Drug or drug class
Reason for considering brand-name
prescribing
Specific
references
4.7.2
Fentanyl patches
Patches are available as matrix and
reservoir formulations; Patient familiarity
with one brand is important. Reservoir
patches (e.g. Tilofyl) 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 (e.g. Durogesic
DTrans, Matrifen).
PCF3 [8],
MHRA [9]
4.8.1
Antiepileptic medicines
Loss of seizure control has been reported
in patients after switching brands of
antiepileptic medicines. Continuity of the
same brand, or the same generic
preparation is recommended for patients
with seizure disorders. (For individual
antiepileptic agents, see below.)
NICE [10],
Epilepsy
Action [11]
4.8.1
Carbamazepine
Different preparations may vary in
bioavailability. Carbamazepine has a
narrow therapeutic index.
(See also ‘Antiepileptic medicines’
above.)
BNF
4.8.1
Lamotrigine
Generic and branded products are
bioequivalent. See also ‘Antiepileptic
medicines’ above.
MHRA [12]
4.8.1
Phenytoin
On the basis of single dose tests there
are no clinically relevant differences in
bioavailability between available
phenytoin sodium tablets and capsules
but there may be a pharmacokinetic basis
for maintaining the same brand of
phenytoin in some patients. Phenytoin
has a narrow therapeutic index.
(See also ‘Antiepileptic medicines’
above.)
4.8.1
Topiramate
Generic and branded products are
bioequivalent. See also ‘Antiepileptic
medicines’ above.
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
Patient familiarity with the same brand is
important; training is required in the use of
specific devices for self-injection.
dm+d
BNF
MHRA [13]
Chapter 6
6.1.1
Insulin
From the NHS Evidence website www.evidence.nhs.uk
BNF
Drug or drug class
Reason for considering brand-name
prescribing
Specific
references
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.
dm+d
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.
dm+d, BNF
Chapter 7
7.3.1
Combined oral contraceptive
Different brands of the same formulation
are available. Patient familiarity with one
brand is important.
-
7.3.2
Progestogen only oral contraceptive
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
Mycophenolate
Generic mycophenolate is considered
bioequivalent to CellCept; but 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, PJ
[14], Renal
News [15]
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, Renal
News [15],
MHRA [16]
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,
MHRA [17]
8.2.4
Interferon pre-filled disposable
injection devices
Patient familiarity with one brand is
important; instructions for use vary
between preparations.
Peginterferon pre-filled disposable
injection devices
From the NHS Evidence website www.evidence.nhs.uk
dm+d
BNF
Drug or drug class
Reason for considering brand-name
prescribing
Specific
references
Chapter 9
9.1.3
Erythropoietin
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,
UKMi [18]
9.1.6
Pegfilgrastim
Patient familiarity with the same brand is
important and training is required in the
use of specific devices for self-injection.
Generic filgrastim has been approved as
a ‘biosimilar’ medicine.
dm+d,
BNF, UKMi
[18]
Filgrastim
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.
-
To aid identification. Products contain
multiple ingredients.
-
To aid identification. Products contain
multiple ingredients. Also, potency of
topical corticosteroids preparations is a
result of the formulation as well as the
corticosteroid.
-
Chapter 12
12.3.5
Saliva replacement products
Chapter 13
13.113.10
Preparations for skin and scalp
conditions containing multiple
ingredients
Limitations

This list of medicines may not be comprehensive and is the opinion of the author.
References
1. Department of Health. Press release: No plans to implement generic substitution of medicines. 14
October 2010. Accessed online at
http://www.dh.gov.uk/en/MediaCentre/Pressreleases/DH_120502 on 5/5/11.
2. Joint Formulary Committee. British National Formulary. 61st ed. London: British Medical
Association and Royal Pharmaceutical Society of Great Britain; 2008. Accessed online via
www.bnf.org on 5/5/2011.
3. Prescribing Support Unit. The Prescribing Toolkit 2009-10. August 2009. Accessed online at
http://www.ic.nhs.uk/webfiles/Services/PSU/2009%20Toolkit_Guide.pdf on 5/5/2011.
4. National Prescribing Centre. Generic prescribing in primary care. MeReC Bulletin 2011; 21(3).
Accessed via www.npc.nhs.uk/merec/other_non_clinical/merec_bulletin_vol21_no3.php on 8/5/11.
5. NHS Business Services Authority. NHS Dictionary of Medicines and Devices Editorial Policy.
Release 2 version 3.0. 23 August 2010. Accessed at
http://195.97.218.30/docs/EBPolicy_NHSdmd_August_2010.doc on 5/5/11.
6. NHS Prescription Services, NHS Business Services Authority. List of items not recommended for
prescribing as a VMP. Personal communication 18/2/2011.
From the NHS Evidence website www.evidence.nhs.uk
7. Medicines and Healthcare products Regulatory Agency. Letter from the Chief Executive.
Beclometasone dipropionate pressurised metered dose inhaler important information. 8 th August
2006. Accessed via
www.mhra.gov.uk/home/idcplg?IdcService=GET_FILE&dDocName=CON2024433&RevisionSelec
tionMethod=LatestReleased on 8/5/2011.
8. Palliative Care Formulary 3. Accessed via www.palliativedrugs.com on 8/5/2011.
9. Medicines and Healthcare products Regulatory Agency. Fentanyl patches: serious and fatal
overdose from dosing errors, accidental exposure, and inappropriate use. Drug Safety Update
2008; 2(2): 2-3. Accessed via
www.mhra.gov.uk/Publications/Safetyguidance/DrugSafetyUpdate/CON025631 on 8/5/2011.
10. National Institute for Clinical Excellence. Clinical guideline 20: The epilepsies – the diagnosis and
management of the epilepsies in adults and children in primary and secondary care. October
2004. Accessed via www.nice.org.uk/Guidance/CG20 on 8/5/2011.
11. Epilepsy Action. Why do my drugs look different? 23rd March 2011. Accessed via
www.epilepsy.org.uk/info/drugs_change.html on 8/5/2011.
12. Department of Health. Treatment for epilepsy: generic lamotrigine. 2 nd March 2005. Accessed via
www.dh.gov.uk/en/Healthcare/Medicinespharmacyandindustry/Prescriptions/DH_4104966 on
8/5/2011.
13. MHRA Public Assessment Report. Topiramate 15mg and 25mg hard capsules. Arrow Generics
Ltd. Accessed at
www.mhra.gov.uk/home/groups/par/documents/websiteresources/con057253.pdf on 8/5/2011.
14. Tynan S and Jerram P. Generic or branded mycophenolate – what strategy should the NHS
adopt? Pharm J 2010; 285 (7630): 659-660.
15. Black H. Implications of generic drugs in renal disease. Renal News 2011; 2: 3-4.
16. Medicines and Healthcare products Regulatory Agency. Information sent to healthcare
professionals October 2010: Capimune (ciclosporin). Accessed via
www.mhra.gov.uk/Safetyinformation/Safetywarningsalertsandrecalls/Safetywarningsandmessages
formedicines/Monthlylistsofinformationforhealthcareprofessionalsonthesafetyofmedicines/CON099
712 on 8/5/2011.
17. Medicines and Healthcare products Regulatory Agency. Tacrolimus (Advagraf and Prograf): risk of
serious medication errors. Drug Safety Update 2009; 2(6): 4-5. Accessed via
www.mhra.gov.uk/Publications/Safetyguidance/DrugSafetyUpdate/CON035989 on 8/5/2011.
18. Gough S. UKMi Medicines Q&A: What are biosimilar medicinal products? 23rd December 2009.
Accessed via www.nelm.nhs.uk/en/NeLM-Area/Evidence/Medicines-Q--A/What-are-biosimilarmedicinal-products/?query=biosimilar&rank=100 on 12/5/11.
Quality Assurance
Prepared by
Karoline Brennan, North West Medicines Information Centre
Date Prepared
February 2009 (partial revision May 2011)
Checked by
Simone Henderson, North West Medicines Information Centre
Christine Proudlove, North West Medicines Information Centre
Date of check
February 2009 (partial revision checked May 2011)
From the NHS Evidence website www.evidence.nhs.uk