Griseofulvin
GRIFULVIN
Pronunciation: gri-see-oe-FUL-vin
“Greasy fulcrum”
What it isAntifungal disrupting fungal microtubules; dermatophyte infections of hair and skin.
Why this oneMicrosporum tinea capitis is the niche where it can outperform terbinafine.
What limits itLong courses and hepatic enzyme induction complicate use; hormonal contraception and warfarin can lose effect.
FDA-approved for
- dermatophyte infections (~1959)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Tinea corporis / cruris / capitis | Adults | 375 mg QD (single or divided) | 375 mg QD | |
| Tinea pedis / unguium (difficult to eradicate) | Adults | 750 mg/day divided | 750 mg/day divided | |
| Tinea infections | Pediatric (~7.3 mg/kg/day) | 16-27 kg: 125-187.5 mg QD; >27 kg: 187.5-375 mg QD | same, single daily dose |
Renal Undefined
Hepatic Undefined
Instructions
- Swallow whole or crush onto 1 tbsp applesauce and swallow immediately without chewing
- Continue until organism eradicated: tinea capitis 4-6 wk, corporis 2-4 wk, pedis 4-8 wk, fingernails ≥4 mo, toenails ≥6 mo
- Not established in children ≤2 years
Available strengths
- tab 125, 165, 250, 500 mg
- susp 125 mg/5 mL
Contraindications
- Pregnancy (reports of conjoined twins with first-trimester use)
- Porphyria
- Hepatocellular failure
Cautions
- Severe skin reactions and hepatic adverse events (post-marketing)
- Hypersensitivity-type reactions may require drug withdrawal
- Photosensitivity; discontinue if granulocytopenia occurs
Adverse reactions
- Skin rashes, urticaria, erythema multiforme-like reactions
- Nausea, vomiting, epigastric distress, diarrhea
- Headache, fatigue, dizziness, insomnia
- Paresthesia of hands/feet after prolonged use
Pregnancy Contraindicated — reports of conjoined twins with first-trimester exposure
Lactation Undefined
Cost
Generic entry1982
NO BOXED WARNINGS
Principal riskIt induces CYP3A4, so contraception fails
Classes and tags
Clinical profile
Legacy pregnancy categoryUnknown / historical label unavailable
Defining liabilityHepatotoxicity and clinically important CYP/QT interactions; organ toxicity varies markedly by agent.
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