ORNIDYL
Clinical safety rating: caution
Comprehensive clinical and safety monograph for ORNIDYL (ORNIDYL).
Irreversible inhibitor of ornithine decarboxylase (ODC), thereby depleting polyamines essential for cell growth and differentiation.
| Metabolism | Metabolized primarily by the liver via unknown pathways; minimal renal excretion of unchanged drug. |
| Excretion | Renal: ~80% as unchanged drug; biliary/fecal: minimal (<5%) |
| Half-life | Terminal half-life: 4–6 hours in normal renal function; prolonged in renal impairment (up to 12–24 hours) |
| Protein binding | ~70% bound to plasma proteins (albumin and globulins) |
| Volume of Distribution | ~0.5 L/kg; indicates moderate extravascular distribution |
| Bioavailability | Oral: ~50–80% (variable due to first-pass metabolism); IV: 100% |
| Onset of Action | IV: Onset within minutes; oral: 1–2 hours |
| Duration of Action | IV: 6–8 hours; oral: 8–12 hours; clinical effect persists for duration of treatment course |
| Molecular Weight | 181.15 |
400 mg/kg/day IV divided every 6 hours for 14 days; alternatively, 100 mg/kg IV every 6 hours for 14 days.
| Dosage form | INJECTABLE |
| Renal impairment | No specific GFR-based guidelines; use with caution in renal impairment due to potential accumulation; consider dose reduction if CrCl <30 mL/min. |
| Liver impairment | No specific Child-Pugh based guidelines; use with caution in hepatic impairment. |
| Pediatric use | Neonates and infants: 100 mg/kg IV every 6 hours for 14 days. Older children: 400 mg/kg/day IV divided every 6 hours for 14 days. |
| Geriatric use | No specific adjustments; use with caution due to age-related renal and hepatic function decline; monitor for adverse effects. |
| 1st trimester | Embryotoxic in animal studies; avoid use due to risk of teratogenicity. |
| 2nd trimester | Potential for fetal harm; use only if benefit outweighs risk. |
| 3rd trimester | Avoid near term due to potential for adverse effects on neonate (e.g., hypotension, electrolyte disturbances). |
Clinical note
Comprehensive clinical and safety monograph for ORNIDYL (ORNIDYL).
| Placental transfer | Crosses the placenta (based on molecular weight and animal studies). |
| Breastfeeding | Excreted into breast milk in small amounts; potential for serious adverse reactions in nursing infants (e.g., bone marrow suppression). Contraindicated during breastfeeding. |
| Lactation Rating |
■ FDA Black Box Warning
WARNING: Thrombocytopenia and anemia have been reported; monitor platelet counts and hemoglobin levels regularly.
| Serious Effects |
Hypersensitivity to eflornithinePregnancyBreastfeedingSevere hepatic impairmentSevere renal impairment
| Precautions | Bone marrow suppression: monitor blood counts frequently, Seizures: may lower seizure threshold; use caution in patients with epilepsy, Ototoxicity: hearing loss reported; audiometry recommended, Hepatotoxicity: monitor liver function tests, Gastrointestinal effects: nausea, vomiting, diarrhea |
| Food/Dietary | No specific food interactions reported. Maintain adequate hydration. Avoid alcohol due to potential hepatotoxicity. |
Loading safety data…
| L5 (Contraindicated) |
| Teratogenic Risk | FDA Pregnancy Category C. No adequate studies in pregnant women. In animal studies, eflornithine (the active ingredient in ORNIDYL) was teratogenic at doses similar to human doses. First trimester: potential teratogenic effects (skeletal abnormalities, embryotoxicity). Second and third trimesters: risk of fetal harm unknown; use only if benefit outweighs risk. |
| Fetal Monitoring | Monitor complete blood counts (CBC) weekly for thrombocytopenia and leukopenia. Monitor liver function tests (LFTs) and renal function. In pregnant patients, consider fetal ultrasound for skeletal development if first trimester exposure. Monitor for signs of ototoxicity and peripheral neuropathy. |
| Fertility Effects | Eflornithine may impair fertility in females and males based on animal studies (reversible ovulatory suppression and decreased spermatogenesis). Human data are lacking. |
| Clinical Pearls |
| Monitor for ototoxicity, especially in patients with renal impairment; eflornithine can cause irreversible hearing loss. Use with caution in patients with hematologic disorders due to risk of myelosuppression. Contraindicated in pregnant women (teratogenic in animal studies). Administer IV infusion over 45-60 minutes; rapid infusion may cause hypotension. |
| Patient Advice | This medication can cause hearing loss; report any ringing in ears or hearing changes immediately. · You may experience hair thinning or loss; this is usually reversible after drug discontinuation. · Avoid pregnancy during treatment; use effective contraception. · Report any signs of infection (fever, sore throat) or easy bruising/bleeding. · Do not stop the medication abruptly; complete full course as prescribed. |