Before using this Q&A, read the disclaimer at www.ukmi.nhs.uk/activities/medicinesQAs/default.asp
Date prepared: April 2015
Toothpastes contain excipients which can cause adverse reactions affecting the mouth and lips, and systemic hypersensitivity.
Excipients most commonly implicated are flavourings such as spearmint, peppermint, fennel, cinnamon and cassia oil, but preservatives, foaming agents, antibacterials, pyrophosphates and essential oils can also cause adverse reactions.
This Medicines Q&A lists toothpastes widely available in the UK and the excipients they contain which have been associated with adverse reactions or may be undesirable.
Background Toothpastes contain a large number of excipients including fluoride, abrasives, detergents, binding agents, humectants, preservatives, colouring agents, antiseptics and flavourings . There are reports that some of these excipients cause adverse oral reactions such as cheilitis (due to allergic or irritant contact dermatitis – ACD and ICD), peri-oral eczema, stomatitis, lichenoid reactions, burning mouth syndrome, loss of taste and systemic reactions such as anaphylaxis, rhinitis and breathing difficulties [1-25]. In a retrospective study of 202 patients referred to a tertiary dermatology centre with eczematous cheilitis, 25.9% of cases were caused by toothpastes, the second most common cause after lip cosmetics .
Excipients most commonly implicated are flavourings (and their active compounds) – spearmint (carvone), peppermint (menthol), fennel (anethole) and cinnamon or cassia oil (cinnamic aldehyde) [1,3,4]. Others that have been reported to cause contact allergic reactions include the antibacterial, triclosan [5,6], foaming agents such as cocamidopropyl betaine [7,8] and sodium lauryl sulphate [9,10], and preservatives such as parabens , polyethylene glycol [7,11] and sodium benzoate . Pyrophosphates in tartar-control toothpastes have caused ICD with ulceration, sloughing, erythema, fissuring and a burning sensation [13,14]. Tartar-control toothpastes containing pyrophosphates can be a particular problem as they contain higher concentrations of flavourings and detergents to mask the bitter taste of these compounds and increase their solubility [13,14]. Essential oils (tea tree oil and propolis) [3,26] and fragrances (limonene and linalool)  have also been reported to cause allergy.
For patients who experience adverse effects that are thought to be due to their toothpaste, changing to another product that does not contain the suspected excipient results in complete resolution of symptoms within a few weeks or months [3,8,13,14,17,18,20,21,28]. If ACD is suspected, patch testing can be helpful in identifying the likely allergen [29,30].
Answer The following table is a list of toothpastes widely available in the UK and the excipients they contain which are associated with irritant or allergic reactions affecting the mouth and lips, or systemic adverse effects. It can be used to choose a suitable product that does not contain excipients suspected to be the cause of adverse reactions. The table also includes fluoride content, and sweeteners and other excipients which may be undesirable.
Key: CAPB cocamidopropyl betaine NS detail not specified