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Boots Mouth Ulcer Gel

Active Ingredient:
lidocaine, cetylpyridinium chloride
THE BOOTS COMPANY PLC See contact details
About Medicine
{healthcare_pro_orange} This information is for use by healthcare professionals
Last updated on emc: 06 Feb 2023
1. Name of the medicinal product

Sore Mouth Gel or Boots Mouth Ulcer Gel

2. Qualitative and quantitative composition

Active ingredients


Lidocaine base

0.6 % w/w

Cetylpyridinium chloride

0.02 % w/w

Excipients of known effect

ethanol (alcohol 96%)

35.00 % v/w

sucrose (refined sugar)

5 % w/w

For a full list of excipients, see section 6.1

3. Pharmaceutical form

Oromucosal Gel

4. Clinical particulars
4.1 Therapeutic indications

For the rapid relief of pain caused by minor recurrent aphthous mouth ulcers.

4.2 Posology and method of administration

For topical application to the mouth and gums.

Adults and children aged 5 months and over

A small quantity of gel to be applied to the sore area with a clean finger every three hours as necessary.

Babies under 5 months

Not suitable.

4.3 Contraindications

Hypersensitivity to the active ingredients or to any of the excipients listed in section 6.1)

Current or past history of methaemoglobinaemia.

4.4 Special warnings and precautions for use

Keep all medicines out of the reach of children.

If symptoms persist for more than seven days consult your doctor or dentist.

Not suitable for treatment of teething in children.

This medicine contains 350 mg of alcohol (ethanol) in each 1g of gel. The amount in 0.2g of this medicine is equivalent to less than 1.6 ml beer or 1.1 ml wine. The small amount of alcohol in this medicine will not have any noticeable effects.

Patients with rare hereditary problems of fructose intolerance, glucose-galactose malabsorption or sucrase-isomaltase insufficiency should not take this medicine.

4.5 Interaction with other medicinal products and other forms of interaction

No clinically significant drug interactions known.

4.6 Pregnancy and lactation

The safety of this product during pregnancy and lactation has not been established. The product is, therefore, not recommended during pregnancy and lactation except under medical supervision.

4.7 Effects on ability to drive and use machines

No adverse effects known.

4.8 Undesirable effects

Hypersensitivity reactions due to lidocaine have been reported rarely and to cetylpyridinium chloride occasionally.

Methaemoglobinaemia has been reported with some local anaesthetics including lidocaine.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at or by searching for MHRA Yellow Card in the Google Play or Apple App Store.

4.9 Overdose

Overdosage with this product is unlikely to constitute a hazard as large amounts of lidocaine or cetylpyridinium chloride are required to produce clinically relevant toxic effects.

Very rarely, methaemoglobinaemia may occur with excessive exposure to some local anaesthetics. This is much more commonly seen with benzocaine and prilocaine than with lidocaine. Risk is increased in patients with hereditary methaemoglobinaemia and when used with other oxidising agents.

5. Pharmacological properties
5.1 Pharmacodynamic properties

Lidocaine is a local anaesthetic of the amide type. Cetylpyridinium chloride is a cationic antiseptic.

5.2 Pharmacokinetic properties

Lidocaine is rapidly absorbed from mucous membranes. The plasma elimination half life is about two hours.

Lidocaine undergoes significant first pass metabolism in the liver and is rapidly de-ethylated to the active metabolite monoethylglycinexylidide and then hydrolysed to various metabolites including glycinexylidide. Less than 10% is excreted unchanged by the kidneys. The metabolites are also excreted in the urine.

5.3 Preclinical safety data

Not applicable.

6. Pharmaceutical particulars
6.1 List of excipients

Refined sugar

Cetomacrogol 1000


Alcohol 96%


Levomenthol synthetic or natural

Star anise oil

Purified water

6.2 Incompatibilities

None stated.

6.3 Shelf life

36 months.

6.4 Special precautions for storage

Store below 25° C.

6.5 Nature and contents of container

A collapsible aluminium tube, internally lacquered with a polyamide/polyimide lacquer system with a membrane seal fitted with a wadless polythene cap or polypropylene cap.

Pack size: 15 gm.

6.6 Special precautions for disposal and other handling

None stated.

7. Marketing authorisation holder

The Boots Company PLC

1 Thane Road West

Nottingham NG2 3AA

8. Marketing authorisation number(s)

PL 00014/0150

9. Date of first authorisation/renewal of the authorisation

Date of First Authorisation:

25 June 1974

Date of Last Renewal:

16 April 2004

10. Date of revision of the text

13th January 2023

Company image
1 Thane Road West, Beeston, Nottingham, NG2 3AA
+44 (0)1159 595 165
+44 (0)1159 592 565