Counterirritants

Date

April 25, 2025

Proper name(s), Common name(s), Source information

References: NIH 2024; ChEBI 2023; RSC 2023; USP-NF 2023; Ph.Eur. 2013; BP 2012; CTFA 2008; Bruneton 1999.
¹All ingredients, except ammonium hydroxide, must be pharmacopoeial grade.
²Synthetic
³Isolate
⁴Extract
⁵Extract from one or more of the Pinus species listed in Table 1.

References: NIH 2024; ChEBI 2023; RSC 2023; USP-NF 2023; Ph.Eur. 2013; BP 2012; Bruneton 1999.
¹All ingredients must be pharmacopoeial grade.
²Synthetic
³Extract
⁴Isolate

Route of Administration

Topical

Dosage Form(s)

All products

• Cream; Emulsion; Foam; Gel; Liniment; Liquid; Oil; Ointment; Salve; Solution; Spray; Spray, suspension; Suspension; Topical liquid; Wipe

Products containing eucalyptus oil, eucalyptol, menthol and/or methyl salicylate as the only counterirritant ingredient(s)

• Patch; Plaster

Use(s) or Purpose(s)

Products containing an ingredient in Table 1

• Temporarily relieves aches and pains/soreness of muscles and joints (associated with one or more of the following: simple backache, lumbago, strains and sprains (involving muscles, tendons, and/or ligaments), and arthritis) (US FDA 2023).

Note that the statements “penetrating pain relief”, “warming pain relief” and/or “cooling pain relief” can be added as additional recommended uses to the Product Licence Application form. However, these statements cannot be used on their own on the product label and must be accompanied by the full recommended use statement above. The terms “cooling sensation” and “warming sensation” are considered non-therapeutic and can therefore be included on the label only, provided they are not misleading.

Dose(s)

Subpopulation(s)

Children 2 to 11 years, Adolescents 12 to 17 years, Adults 18 years and older.

Quantity(ies)

¹Quantities are expressed in percentage volume by volume (% v/v), percentage weight by volume (% w/v) or percentage weight by weight (% w/w). References: JC 2024; US FDA 2023; AU TGA 2007; Janjua et al. 2004; ESCOP 2003; APhA 2002; WHO 2002; Blumenthal et al. 2000; CPhA 1996; Mathias et al. 1995.

¹Quantities are expressed in percentage volume by volume (% v/v), percentage weight by volume (% w/v) or percentage weight by weight (% w/w). Reference: US FDA 1979.

Permitted combinations

• Clove essential oil and thymol must be used in combinations with other medicinal ingredients in Table 1, as they cannot support the efficacy of the product on their own (US FDA 2023).
• Any ingredient from Table 5 can be combined with other ingredients from the table provided that the combination contains only one ingredient from each group (except for group B1) and that each ingredient is within the quantities given in Tables 3 and 4 (US FDA 2023).
• Group B1 ingredients may be used in combination with each other, and this may be combined with any ingredients from the table provided that combination contains only one ingredient from each of the other groups.

¹See Appendix 1 for grouping rationale.
²Permitted combinations for all groups are supported by US FDA 2023, except for Group E which is supported by RSC 2023, Sweetman 2017, and Leung and Foster 2003.

Direction(s) for use

All products

• Do not apply to wounds or damaged skin (US FDA 2023).
• Do not tightly bandage (US FDA 2023).
• Do not apply with external heat, such as an electric heating pad, as this may result in excessive skin irritation or skin burn (Pray 2006; APhA 2002).
• Supervise children when they use this product (Ragucci et al. 2007; Love et al. 2004).

Products in cream, emulsion, foam, gel, liniment, liquid, oil, ointment, salve, solution, suspension, topical liquid or wipe dosage form

• Apply thinly and evenly to affected area(s), up to 4 times per day. Rub and/or massage into skin until solution vanishes (US FDA 2023).

Products in plaster or patch dosage form

• Apply 1 plaster/patch to affected area(s), up to 3 times per day. Do not leave on skin for more than a total of 8 hours per day (Higashi et al. 2010).

Products in spray or spray, suspension dosage form

• Apply thinly and evenly to affected area(s), up to 4 times per day. Rub and/or massage into skin until solution vanishes. Avoid inhaling or exposing others to spray (US FDA 2023; APhA 2002).

Duration(s) of Use

Products containing capsaicin as a single medicinal ingredient

• May take 1-2 weeks to produce beneficial effects.
• Ask a health care practitioner/health care provider/health care professional/doctor/physician for use beyond 6 weeks (Sweetman 2017; CPS 2008; APhA 2002; CPhA 1996).

All other products (including multiple ingredient products containing capsaicin)

Ask a health care practitioner/health care provider/health care professional/doctor/physician for use beyond 7 days (US FDA 2023).

Risk Information

Caution(s) and warning(s)

All products

• For external use only (US FDA 2023).
• When using this product avoid contact with the eyes and mucous membranes. If contact occurs, rinse thoroughly with water (US FDA 2023).
• Stop use and ask a health care practitioner/health care provider/health care professional/doctor/physician if symptoms persist, worsen, or re-occur within a few days (US FDA 2023; CPhA 1996).
• Keep out of reach of children. If swallowed, call a poison control centre or get medical help right away (CPS 2008; HC 2004).

Products containing camphor, menthol, and/or methyl salicylate

Ask a health care practitioner/health care provider/health care professional/doctor/physician before use if you are pregnant or breastfeeding (Brinker 2010).

Products containing methyl salicylate and/or methyl nicotinate

Ask a health care practitioner/health care provider/health care professional/doctor/physician before use if you are taking blood thinners (Sweetman 2017; APhA 2002).

Products containing methyl nicotinate

Ask a health care practitioner/health care provider/health care professional/doctor/physician before use if you are taking medications or health products that cause dilation of blood vessels (APhA 2002).

Contraindication(s)

Products containing more than 0.5% of clove essential oil

Do not use if you are prone to allergic reactions, eczema or unusual skin reactions (Tisserand and Young 2014).

Known adverse reaction(s)

All products

Stop use if hypersensitivity/allergy, rashes and/or burning discomfort occur (Sweetman 2017; Zhang et al. 2008; Hoffman 2003; APhA 2002; McCleane 2000).

Products containing capsaicin

Stop use if headache and/or redness occur (Zhang et al. 2008; APhA 2002; McCleane 2000).

Products containing menthol

Stop use and get medical help right away if you experience pain, swelling or blistering, as rare but serious burns can occur (HC 2017).

Non-medicinal ingredients

• Ingredients must be chosen from the current Natural Health Products Ingredients Database (NHPID) and must meet the limitations outlined in that database and in the current Cosmetic Ingredient Hotlist, when relevant.
• As per section 1.5 of the Pathway for licensing natural health products making modern health claims guidance document, non-medicinal ingredients should not contribute to the pharmacological effect of a product. Thus, products supported by this monograph cannot include as a non-medicinal ingredient any plant extracts or essential oils containing the constituents allyl isothiocyanate, camphor, capsaicin, eucalyptol, menthol, or methyl salicylate, including (but not limited to) extracts or essential oils from Armoracia rusticana, Betula lenta, Brassica nigra, Brassica oleracea var. capitata, Capsicum annum, Capsicum frutescens, Cinnamomum camphora, Eucalyptus globulus, Eucalyptus radiata, Eucalyptus smithii, Gaultheria procumbens Mentha arvensis, Mentha canadensis, or Mentha x piperita.

Storage conditions

Must be established in accordance with the requirements described in the Natural Health Products Regulations.

Information for industry (not for labelling)

• Store in airtight, light-resistant container at room temperature (USP-NF 2023; Ph.Eur. 2013; BP 2012).
• To mitigate the potential risk to the health of children, child-resistant packaging/containers should be used (AU TGA 2017).

Specifications

• The finished product specifications must be established in accordance with the requirements described in the Natural and Non-prescription Health Products Directorate (NNHPD) Quality of Natural Health Products Guide.
• The medicinal ingredient must comply with the requirements outlined in the NHPID.
• The medicinal ingredient must be of pharmacopoeial grade.

References Cited

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Appendix 1

¹These are not uses or purposes.