Important aspects of prescribing information relevant to primary healthcare are covered in this section specifically for the drugs recommended in this CKS topic. For further information on contraindications, cautions, drug interactions, and adverse effects, see the electronic Medicines Compendium (eMC) (http://emc.medicines.org.uk), or the British National Formulary (BNF) (www.bnf.org).

• Hydrocortisone 2.5 mg lozenges are licensed for use in aphthous ulcers [BNF 53, 2007]. Triamcinolone in an adhesive paste (Adcortyl in Orabase^®) has been discontinued.
• Encourage individuals with prodromal symptoms to apply corticosteroids at this stage. Otherwise, corticosteroids should be applied as soon as the ulcers appear [Scully et al, 2003].
• Concerns have been raised that long-term or repeated application could cause adrenal suppression. However, there is little evidence that even some of the more potent steroids (such as fluocinonide or betamethasone) cause significant problems in this respect [Scully et al, 2002].

• Chlorhexidine is the antimicrobial mouthwash of choice. It has the most evidence to support its use, and is recommended in the literature by experts [Scully et al, 2003].
• Chlorhexidine can stain teeth brown when used regularly. The stain is not usually permanent, and can be reduced by avoiding drinks that contain tannin (e.g. tea, coffee, or red wine), and by brushing teeth before, rather than after, use. However, the mouth should be rinsed well after tooth brushing as some ingredients in toothpaste can inactivate chlorhexidine [ABPI Medicines Compendium, 2005].
• Tetracycline mouthwash has been used for severe recurrent aphthous ulceration. Although it may reduce the duration and severity of ulcers, it can cause oral candidiasis and a burning-like sensation of the pharynx [Porter et al, 2000]. Tetracycline capsules are no longer available in the UK so doxycycline is usually substituted instead; the contents of a doxycycline 100 mg capsule are dispersed in water and rinsed around the mouth four times a day.
• Doxycycline mouthwash should not be used in pregnant or breastfeeding women, or in children.

• Topical analgesics may provide relief from very painful ulcers, but their duration of action is short-lived.
• Benzydamine hydrochloride is available as a mouthwash or spray.
• The mouthwash can cause stinging. This can be reduced by diluting the mouthwash in an equal volume of water before use.
• The spray is useful for difficult to use areas, and is licensed for use in children.