Is Griseofulvin (griseofulvin) safe for use in children?

Griseofulvin Safety and Use in Children

Griseofulvin is safe and remains the only licensed oral antifungal agent for treating tinea capitis in children in the UK, with over 50 years of clinical experience demonstrating its safety profile, particularly in pediatric populations. 1

Licensing and Regulatory Status

• Griseofulvin is the only licensed product for treating tinea capitis in children in the UK, approved for use from 1 month of age. 1
• The FDA confirms griseofulvin has been used for over 40 years with an established safety record in pediatric populations. 2
• Griseofulvin is FDA-approved for children and is the only antifungal agent licensed for pediatric onychomycosis. 1

Safety Profile in Children

• Side effects in children are generally mild and infrequent, with gastrointestinal disturbances and rashes occurring in less than 8% of patients, and only 0.8% requiring treatment discontinuation. 1
• The drug is particularly well-tolerated in children compared to adults, with minor side effects including headaches, gastrointestinal reactions, and cutaneous eruptions. 3
• Griseofulvin has the least known drug interactions among oral antifungals used for tinea capitis, enhancing its safety profile in children who may be on other medications. 4

Dosing in Pediatric Populations

• The standard licensed dose is 20 mg/kg daily in single or divided doses for 6-8 weeks in children weighing less than 50 kg. 1
• Doses may be increased up to 25 mg/kg daily for prolonged periods in resistant cases. 1
• Administering griseofulvin with fatty meals or milk significantly enhances absorption—in children aged 19 months to 11 years, giving 10 mg/kg with milk resulted in peak serum concentrations four-fold greater than when given alone. 2

Contraindications and Drug Interactions

• Contraindicated in children with lupus erythematosus, porphyria, or severe liver disease. 1
• Important drug interactions include: plasma concentration decreased by rifampicin and increased by cimetidine. 1
• Additional interactions noted with phenobarbital, anticoagulants, and oral contraceptives (relevant for adolescents). 3

Efficacy Considerations by Organism

• Griseofulvin demonstrates 88.5% response rates for Microsporum species but only 67.9% for Trichophyton species, requiring higher doses (up to 25 mg/kg) and longer treatment durations (12-18 weeks) for Trichophyton infections. 1
• For Microsporum canis infections specifically, 8 weeks of griseofulvin treatment is significantly more effective than 4 weeks of terbinafine. 1
• Clinical response rates of 80-90% have been reported in controlled studies of tinea capitis in children. 3

Comparative Safety with Newer Agents

• Griseofulvin has a longer track record of safety than newer antifungals (terbinafine, itraconazole, fluconazole), making it the preferred choice when safety is the primary concern. 4
• In a head-to-head comparison, none of the itraconazole-treated children experienced side effects, while 2 of 17 griseofulvin patients discontinued therapy due to vomiting, though overall cure rates were equivalent (88% for both). 5
• Large controlled trials continue to show griseofulvin exhibits equal or greater efficacy compared to newer agents, with a well-established safety profile. 4

Practical Advantages for Pediatric Use

• Suspension formulations (where available) are more palatable to children and allow more accurate dosage adjustments based on weight. 1
• The drug is deposited in keratin precursor cells and has greater affinity for diseased tissue, becoming tightly bound to new keratin that is highly resistant to fungal invasion. 2
• Griseofulvin concentrations in skin decline less rapidly than plasma levels after discontinuation, providing sustained antifungal effect. 2

Important Clinical Caveats

• Treatment duration is prolonged (6-8 weeks minimum, up to 12-18 weeks for Trichophyton), which may affect compliance—this is the primary disadvantage compared to newer agents. 1
• The definitive endpoint for adequate treatment must be mycological cure rather than clinical response alone; follow-up with repeat mycology sampling is recommended. 1
• For anthropophilic species like Trichophyton tonsurans, screen and treat all family members, as over 50% may be affected, leading to high recurrence rates if untreated. 1