Griseofulvin

Griseofulvin

  • Pregnancy Category C

Formulations

  • Ultramicrosize & microsize tablets, & oral suspension (125mg / 5 mL)

Dosing

Tinea capitis (children):

  • 10-15mg/kg daily x 6-8 weeks (ultramicrosize)

or 

  • 20-25mg/kg daily x 6-8 weeks (microsize)

Tinea corporis & cruris

  • 250 mg BID x 2-4 weeks

Tinea pedis

  • 660-750 mg daily x 4-8 weeks

Tinea imbricate

  • 500 mg BID x 4-6 weeks

  • Disrupts microtubule (interferes with tubulin), thereby inhibiting mitosis in dermatophytes; in ectothrix, works better than terbinafine as excreted in sweat

  • Bioavailability ~25-70%
  • Better absorbed with fatty meal
  • Hepatic metabolism
  • Renal excretions (50%) & fecal elimination

FDA

  • Dermatophyte onychomycosis, tinea corporis, pedis, capitis*

* Treatment of choice for tinea capitis in children secondary to M. Canis

Off-label

  • Tinea imbricata

  • Porphyrias: acute intermittent porphyria, variegate porphyria & porphyria cutanea tarda 
  • Liver disease
  • Pregnancy

  • Headaches, paresthesias, gastrointestinal disturbance

Dermatologic

  • photosensitivity, subacute cutaneous lupus, porphyrias, fixed drug eruption

* For further reading refer to a pharmacology source

  • Not used for nail infections as low affinity for keratin results in long treatment duration & low efficacy (e.g. 9-12 months) 
  • Periodic urea/creatinine, liver function tests & complete blood count throughout treatment