Fluconazole/tioconazole

Author Information

An event is serious (based on the ICH definition) when the patient outcome is:

• * death

• * life-threatening

• * hospitalisation

• * disability

• * congenital anomaly

• * other medically important event

A 54-year-old woman developed allergic contact dermatitis following cross reactivity during treatment with tioconazole and fluconazole for onychomycosis [not all dosages stated].

The woman was referred to hospital for an intolerable pruriginous cutaneous rash. Cutaneous examination showed eczematous patches involving the lower and upper limbs and feet with dystrophic and onycholytic toenails. Her history showed nail lesions which had appeared following the removal of a semi-permanent nail lacquer. Onychomycosis was suspected and the pharmacist recommended application of 28% tioconazole solution [Trosyd nail solution] daily. Twenty days later, she developed vesciculous and erythematous reaction with itching on her periungual tissues. She returned to pharmacist due to fear of going to doctor during the COVID-19 pandemic suspecting extended fungal infection. The pharmacist suggested applying tioconazole 1% cream. After two days, she developed an extended eczematous dermatitis on the feet and lower limbs. She called her doctor and reported a suspicion of widespread fungal infection. Afterwards, oral fluconazole and diflucortolone valerate/isoconazole nitrate were prescribed over phone. An extension of the cutaneous eruption was noted 48 hours later. She had no previous history of any allergy. Patch test was performed with the baseline series of the TRUE Test (miconazole 1% aq., econazole nitrate 1% aq., tioconazole 1% pet), diflucortolone valerate/isoconazole nitrate cream and tioconazole 28% nail solution. Fluconazole was unavailable and was not tested. Readings on day 2 and day 4 revealed positive reactions to tioconazole 1%, nickel sulfate 5% and tioconazole 28% nail lacquer. A diagnosis of allergic contact dermatitis following cross reactivity with topical tioconazole and oral fluconazole was made [outcome not stated].