CKS found no evidence to guide the choice of antifungal drug. This recommendation is based on the fact that in the UK the most prevalent infection is now Trichophyton tonsurans, especially in cities [HPA, 2007]. However, feedback from experts reviewing this topic suggests that outside urban areas, or in rural areas, Microsporum canis is the most common organism, although infections are sporadic.

Terbinafine and griseofulvin

• There is no evidence from placebo-controlled trials to indicate that terbinafine is an effective treatment for scalp ringworm, however there is limited indirect evidence from comparative studies with griseofulvin to support its use.
• Terbinafine is well-documented as a treatment for Trichophyton infections, and is increasingly recommended as a first-line treatment for T. tonsurans infections [Gupta et al, 2004]. Its role in the treatment of Microsporum infections is uncertain [BNF for Children, 2008; BNF 57, 2009]. It appears to be less effective against Microsporum than Trichophyton although there is little in vitro evidence to support this [HPA, 2007]. Although terbinafine is not licensed for the treatment of scalp ringworm, adverse effects are usually mild and transient, and there are fewer drug interactions than with azole antifungals (itraconazole, fluconazole, and ketoconazole) [Gupta et al, 2004].
• Griseofulvin: there are no placebo-controlled trials and only limited evidence from comparative trials to support the use of griseofulvin for scalp ringworm. However, it has been in use for many years and is generally regarded as an effective treatment. It is effective against most organisms that cause tinea capitis, although T. tonsurans infection has a variable response and may need a longer duration of treatment [HPA, 2007]. It is the only oral antifungal drug that is licensed for the treatment of scalp ringworm.
• A recent meta-analysis showed no significant difference in tolerability or adverse effects between griseofulvin and terbinafine [Andrews and Burns, 2008].

Drugs not recommended

• Itraconazole and fluconazole are not recommended for the treatment of scalp ringworm as there are limited trial data on effectiveness and safety [Andrews and Burns, 2008] and they are not licensed for this condition.
• The Committee on Safety of Medicines has advised caution when prescribing itraconazole to people at high risk of heart failure (for example older people, those with cardiac disease, people receiving negative inotropic drugs such as calcium-channel blockers, and people receiving high doses or long treatment courses of itraconazole) [BNF 57, 2009].
• Itraconazole is not recommended for use in children or in older people due to the lack of data on its safety and efficacy. Very rare cases of serious hepatotoxicity have been reported, including some cases of fatal acute liver failure [ABPI Medicines Compendium, 2009].
• Oral ketoconazole should only be initiated by a physician who is experienced in the management of fungal infections because of the risk of serious hepatotoxicity. It should only be prescribed for the treatment of dermatophytosis that cannot be treated topically because of the site, extent of the lesion, or deep infection of the skin, in people resistant to or intolerant of both fluconazole and itraconazole [MHRA, 2008].