Medicines Q&As
Q&A 332.1
What are the differences between non-oral mesalazine
preparations?
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: 15th June 2012
Background
Mesalazine is an aminosalicylate that is used routinely to induce and maintain remission in chronic
inflammatory bowel disease – ulcerative colitis (UC) and Crohn’s disease. Acute mild to moderate
disease affecting the rectum (proctitis) or the recto-sigmoid is treated initially with local application of
an aminosalicylate. Diffuse inflammatory bowel disease or disease that does not respond to local
therapy requires oral treatment. A combination of a local and an oral aminosalicylate can be used in
proctitis or distal colitis. (1) The locally acting preparations that are currently available are liquid and
foam enemas and suppositories which are inserted in to the rectum. Available formulations have
differences in licensed indications, strengths, and dose frequency. (2-9)
Answer
There are various differences between the 4 enema products (2, 4, 6, 8) and the 3 brands of
suppositories. (3, 5, 7, 9) These are set out in table 1 and 2 below.
Licensed indication
All the rectal products are licensed for treatment of UC distal disease, however there are slight
differences between them. (2-9) Distal disease refers to disease up to the sigmoid descending
junction, including that limited to the rectum (proctitis). (10)
Salofalk foam and liquid enemas are for treatment of active, mild UC of the sigmoid colon and rectum.
(6, 8) The 2g enema can also be used for colitis in the descending colon and prophylaxis of colitis
attacks. (8) Salofalk suppositories are indicated for treatment of acute mild and moderate UC in the
rectum. (7, 9) The 500mg suppositories can also be used where there is colitis in the sigmoid colon
and descending colon. (9) Asacol foam enema and suppositories are licensed for treatment of mild to
moderate acute exacerbations. (2, 3) The suppositories are also licensed for maintenance of
remission. (3) The licensed indication for the Pentasa liquid enema is treatment of UC affecting the
distal colon and rectum. (4) The licence for the suppositories is for treatment of ulcerative proctitis,
which is disease limited to the rectum. (5)
Strength & formulation
There are 2 strengths of enema products - 1g and 2g. These are presented in 2 different formulations,
a pressurised canister which administers a dose in a stiff foam or a liquid enema (either 1g in 100ml
or 2g in 59ml). (2, 4, 6, 8)
There is only one strength of the Pentasa suppositories - 1g, whereas there are two strengths of
Asacol suppositories - 250mg and 500mg and Salofalk suppositories - 500mg and 1g. (3, 5, 7, 9)
A MeReC bulletin in 2011 suggested that the proximal extent of the inflammation and patient
preference, including ease of insertion or retention of enemas, should determine the topical
formulation chosen. Suppositories are indicated for disease to the rectosigmoid junction because they
deliver the drug more effectively to the rectum than enemas, whereas foam enemas usually treat up
to the proximal sigmoid colon and liquid enemas can deliver medication as proximal as the splenic
flexure in most patients. Foam and liquid enemas appear to be equally effective in treating patients
with proximal ulcerative colitis, but generally foam enemas are preferred because they are easier to
administer and retention is more comfortable. Suppositories are usually better tolerated than enemas.
(10)
Dose frequency
The products which have a strength of 1g and 2g are given once daily, preferably at bedtime. (2, 4-8)
The 500mg and 250mg suppositories are inserted at regular intervals, (up to 3-6 times) throughout
the day with the last dose at bedtime. (3, 9)
From the NHS Evidence website www.evidence.nhs.uk
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Medicines Q&As
Pharmacokinetics
Absorption from mesalazine rectal dosage forms varies widely and is affected by factors such as the
dose and the formulation; mean absorption of around 10 to 30% of a rectal dose has been reported.
(11)
Table 1 – Comparison of Asacol, Pentasa and Salofalk rectal enemas
Brand
Formulation
Strength
Licensed
indications
Adult dose
frequency
Asacol (2)
Foam enema in a
pressurised
canister containing
14 doses.
1g per metered
dose
Mild to moderate
acute
exacerbations of
UC affecting the
distal colon.
Pentasa (4)
Liquid enema in
single use bottles.
Salofalk (8)
Liquid enema in
single use bottles.
1g in 100ml
Salofolk (6)
Foam enema in a
pressurised
canister containing
14 doses.
1g per actuation
Treatment of UC
affecting the distal
colon and rectum.
Active, mild UC of
the sigmoid colon
and rectum.
1g (one enema)
once daily at
bedtime.
Two metered
applications (2g)
once daily at
bedtime for 4-6
weeks. Can also
administer in
divided doses – 1
at bedtime and 1
during the night or
in the morning if
the patient has
difficulty in holding
in 2 doses at once
Not licensed for
use in children
under 18 years.
Treatment and
prophylaxis of acute
attacks of mild UC
in the rectum,
sigmoid colon &
descending colon.
2g (one enema)
once daily at
bedtime.
Disease affecting
the rectosigmoid
region: 1g (1 dose)
once daily for 4-6
weeks.
Disease affecting
the descending
colon: 2g (2
doses) once daily
for 4-6 weeks.
Use in
children
Adverse
effects related
to
administration
Not licensed for
use in children
under 18 years.
Not licensed for
use in children
under 18 years.
Unlicensed use:
child 12-18 years:
dose as for adults
as above. (12)
Child 12-18 years:
dose as for adults
as above. (12)
Local irritation
Pruritus, rectal
discomfort and
urge to defeacate.
Unlicensed use:
child 12-18 years:
dose as for adults
as above. (12)
Abdominal
distension, anal
discomfort,
application site
irritation, painful
rectal tenesmus.
From the NHS Evidence website www.evidence.nhs.uk
2g in 59ml
Little experience,
only limited
documentation for
an effect in
children. Not
licensed for use in
children under 18
years.
Unlicensed use:
child 12-18 years:
dose as for adults
as above. (12)
None listed in
summary of product
characteristics.
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Medicines Q&As
Table 2 - Comparison of Asacol, Pentasa and Salofalk rectal suppositories
Brand
Formulation
Strength
Licensed
indications
Adult dose
frequency
Use in
children
Adverse
effects related
to
administration
Asacol (3)
Suppositories
250mg and 500mg
Mild to moderate acute
exacerbations of UC,
particularly those
affecting the distal colon.
Maintenance of
remission in UC.
250mg: 3 – 6
suppositories per day in
divided doses, with the
last dose at bedtime.
500mg: maximum of 3
suppositories per day in
divided doses, with the
last dose at bedtime.
Not licensed for use in
children under 18 years.
Pentasa (5)
Suppositories
1g
Treatment of ulcerative
proctitis.
Salofalk (7, 9)
Suppositories
500mg & 1g
Active, mild to moderate
UC of the rectum.
500mg: can also use if UC
in the sigmoid colon and
descending colon.
Acute treatment: 1
suppository daily for 2-4
weeks.
Maintenance treatment: 1
suppository daily
500mg: 1-2 suppositories,
2-3 times daily.
1g: 1 suppository daily,
preferably at bedtime.
Duration of use to be
determined by the
physician.
Not licensed for use in
children under 15 years.
Unlicensed use: child 1218 years: 250mg- 500mg
3 times daily with last
dose at bedtime. (12)
Child 12-18 years: dose
as for adults as above.
Dose unlicensed in
children 12-14 years. (12)
Little experience, only
limited documentation for
an effect in children. Not
licensed for use in children
under 18 years.
Local irritation
Pruritus, rectal discomfort
and urge to defeacate
Unlicensed use: child 1218 years: 500mg
suppositories only. 0.5-1g
2-3 times daily, adjusted
according to response.
(12)
None listed in summary of
product characteristics
Guidance for use
A review of the delivery and efficacy of topical mesalazine therapy in the treatment of UC published in
2011 concluded that there is strong evidence from randomised controlled trials to support use of
topical mesalazine as a first line treatment for patients with mildly to moderately active distal UC.
There is supportive data to suggest that topical therapy, particularly suspensions should be used as
an adjunct to the treatment of extensive disease in the first 4 weeks of therapy. The choice of dosage
form should reflect both the proximal disease extent and patient preference. (13)
The 2011 British Society of Gastroenterology guidelines for the management of inflammatory bowel
disease in adults do not make any specific recommendations for use of rectal aminosalicylates for
treatment of UC. (14)
A MeReC Bulletin addressed common questions around medicines used for inflammatory bowel
disease (IBD) in 2011. (10) The bulletin states that aminosalicylates are considered first-line drugs for
patients with mild to moderate ulcerative colitis. They are effective for inducing and maintaining
remission in ulcerative colitis. The choice of drug and preparation in IBD depends on its safety,
effectiveness, cost and patient factors. Patient factors include the current disease activity, area of the
GI tract affected (e.g. proctitis, recto-sigmoid, or extensive), patient preference and adherence, which
may also influence the dosing frequency chosen. Rectal aminosalicylates are also added to oral
treatment in mild to moderate extensive ulcerative colitis.
From the NHS Evidence website www.evidence.nhs.uk
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Medicines Q&As
Summary
 There are 9 non-oral mesalazine preparations – 4 enemas and 5 suppositories which have slightly






different licences for treatment of ulcerative colitis (UC) distal disease. Distal disease refers to
disease up to the sigmoid descending junction, including that limited to the rectum (proctitis).
The enema products are 1g or 2g in strength, but are presented in 2 different formulations, a
pressurised canister which administers a dose in a stiff foam or a liquid enema (1g/100ml or
2g/59ml). There are 3 strengths of suppositories - 1g, 500mg and 250mg.
All the 1g and 2g products are given once daily, preferably at bedtime. The 500mg and 250mg
suppositories are inserted up to 3 to 6 times throughout the day with the last dose at bedtime.
Absorption from mesalazine rectal dosage forms varies widely and is affected by factors such as
the dose and the formulation; mean absorption of around 10 to 30% of a rectal dose has been
reported.
There is strong evidence from randomised controlled trials to support use of topical mesalazine as
a first line treatment for patients with mildly to moderately active distal UC.
Guidelines and reviews of inflammatory bowel disease do not differentiate between topical
mesalazine therapies or specify which one to use.
The choice of dosage form should reflect the current disease activity, area of the GI tract affected
(e.g. proctitis, recto-sigmoid, or extensive), patient preference and adherence, which may also
influence the dosing frequency chosen and cost.
Limitations
This information is only applicable to the mesalazine products which are for rectal use. Information on
mesalazine tablets is available in medicines Q&A 67.4.
References
1. Martin J, editor. British National Formulary No 64. London: British Medical Association and The
Royal Pharmaceutical Society of Great Britain; March 2012. Accessed 26/10/12 via
http://www.bnf.org/bnf/
2. Summary of Product Characteristics. Asacol Foam Enema, Warner Chilcott UK Limited. Date last
updated 01/12/10. Accessed 12/06/12 via http://www.emc.medicines.org.uk.
3. Summary of Product Characteristics. Asacol Suppositories 250mg & 500mg, Warner Chilcott UK
Limited. Date last updated 06/10/10. Accessed 12/06/12 via http://www.emc.medicines.org.uk.
4. Summary of Product Characteristics. Pentasa Mesalazine Enema, Ferring Pharmaceuticals Ltd.
Date last updated 18/02/05. Accessed 12/06/12 via http://www.emc.medicines.org.uk.
5. Summary of Product Characteristics. Pentasa Suppositories 1g, Ferring Pharmaceuticals Ltd. Date
last updated 01/09/05. Accessed 12/06/12 via http://www.emc.medicines.org.uk.
6. Summary of Product Characteristics. Salofalk 1g/actuation Rectal Foam. Dr Falk Pharma UK Ltd
Date last updated 06/03/12. Accessed 12/06/12 via http://www.emc.medicines.org.uk.
7. Summary of Product Characteristics. Salofalk 1g Suppositories. Dr Falk Pharma UK Ltd. Date last
updated 06/03/12. Accessed 12/06/12 via http://www.emc.medicines.org.uk.
8. Summary of Product Characteristics. Salofalk Enema 2g. Dr Falk Pharma UK Ltd. Date last
updated 07/03/12. Accessed 25/10/12 via http://www.emc.medicines.org.uk.
9. Summary of Product Characteristics. Salofalk Suppositories 500mg. Dr Falk Pharma UK Ltd. Date
last updated 08/03/12. Accessed 25/10/12 via http://www.emc.medicines.org.uk.
10. Common questions around medicines used for inflammatory bowel disease. MeReC Bulletin 2011;
21 (4). http://www.npc.nhs.uk/merec/other_non_clinical/resources/merec_bulletin_vol21_no4.pdf
11. Martindale Sweetman S, editor. Martindale: The Complete Drug Reference 37th ed. Mesalazine.
Date of revision of the text 05/12/11. Accessed 12/06/12 via www.medicinescomplete.com.
12. BNF –C Martin J, editor. BNF for Children 2012-13. London: British Medical Association, the Royal
Pharmaceutical Society of Great Britain, the Royal College of Paediatrics and Child Health, and
the Neonatal and Paediatric Pharmacists Group. Accessed 26/10/12 via http://bnfc.org/bnfc/
13. Harris MS, Lichtenstein GR. Review article: delivery and efficacy of topical 5-aminosalicylic acid
(mesalazine) therapy in the treatment of ulcerative colitis. Alimentary Pharmacology and
Therapeutics 2011; 33: 996-1009.
14. Mowat C; Cole A; Windsor A; Ahmad T; et al. Guidelines for the management of inflammatory
bowel disease in adults. Gut 2011; 60 (5): 571-607
http://www.bsg.org.uk/images/stories/docs/clinical/guidelines/ibd/ibd_2011.pdf
From the NHS Evidence website www.evidence.nhs.uk
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Medicines Q&As
Quality Assurance
Prepared by
Katie Smith, East Anglia Medicines Information Service
Date Prepared
15th June 2012 (date of partial revision 26th October 2012)
Checked by
Sarah Cavanagh, East Anglia Medicines Information Service
Date of check
26th June 2012 (partial revision checked 26th October 2012)
Search strategy

In-house enquiry database, search term: mesalazine

British National Formulary, No. 63, London: British Medical Association and The Royal
Pharmaceutical Society of Great Britain, March 2012, search term: mesalazine

Martindale, The Complete Drug Reference. Pharmaceutical Press. Accessed via
www.medicinescomplete.com, search term: mesalazine

Electronic Medicines Compendium, accessed via www.emc.medicines.org.uk, search term:
mesalazine

National Prescribing Centre, accessed via http://www.npc.nhs.uk/merec/

The Cochrane Library, accessed via http://www.library.nhs.uk/, search term: mesalazine,
ulcerative colitis

IDISweb, search terms: Results of: Drug(s): "MESALAMINE 56400007" and Disease(s):
"PROCTOCOLITIS, IDIOPATHIC 556." and Descriptor(s): "ADM RECTAL 101"

Medline, 1950 to date, search terms: MESALAMINE/ad [ad=Administration & Dosage] AND
[COLITIS, ULCERATIVE/dt [dt=Drug Therapy] OR PROCTOCOLITIS/dt [dt=Drug Therapy]]
[Limit to: English Language and Humans and Publication Year 2009-Current]

Embase, 1980 to date, search terms: MESALAZINE/rc [rc=Rectal Drug Administration]AND
ULCERATIVE COLITIS/dt [dt=Drug Therapy] [Limit to: Human and English Language and
Publication Year 2009-Current]
From the NHS Evidence website www.evidence.nhs.uk
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