Dilantin Infatabs

— THERAPEUTIC CATEGORIES —
  • Seizure disorders

Dilantin Infatabs Generic Name & Formulations

General Description

Phenytoin 50mg; chewable tabs.

Pharmacological Class

Hydantoin.

How Supplied

Caps 30mg—100; 100mg—100, 1000; Tabs—100; Susp—8oz

Manufacturer

Generic Availability

YES

Dilantin Infatabs Indications

Indications

Tonic-clonic, psychomotor and neurosurgically induced seizures.

Dilantin Infatabs Dosage and Administration

Adult

May be chewed or swallowed whole. Initially 2 tabs 3 times daily. Maintenance dose: 6–8 tabs daily in divided doses; may increase to 12 tabs daily if necessary.

Children

Initially 5mg/kg per day in 2–3 equally divided doses. Increase weekly if needed. Usual maintenance: 4–8mg/kg per day; max 300mg daily.

Dilantin Infatabs Contraindications

Contraindications

History of prior acute hepatotoxicity due to phenytoin. Concomitant delavirdine.

Dilantin Infatabs Boxed Warnings

Not Applicable

Dilantin Infatabs Warnings/Precautions

Warnings/Precautions

Suicidal tendencies (monitor). Diabetes. Discontinue if acute hepatotoxicity occurs; do not restart. Monitor serum levels when switching between sodium salt of phenytoin (caps) and free acid form (suspension, Infatabs). Discontinue and evaluate at the 1st sign of a rash. Increased risk of SJS/TEN if positive for HLA-B*1502 or in CYP2C9*3 carriers (esp. Asian ancestry); consider avoiding as an alternative for carbamazepine. Adjust dose gradually. Angioedema. Underlying cardiac disease. Use proper dental hygiene. Hormonal contraception. Monitor bone mineral density with chronic use. Porphyria. Intermediate or poor CYP2C9 metabolizers. Renal and/or hepatic impairment. Hypoalbuminemia. Elderly. Debilitated. Pregnancy: avoid. Nursing mothers: not recommended.

Dilantin Infatabs Pharmacokinetics

See Literature

Dilantin Infatabs Interactions

Interactions

Potentiated by acute alcohol ingestion, amiodarone, antiepileptic agents (eg, ethosuximide, felbamate, oxcarbazepine, methsuximide, topiramate), azoles (eg, fluconazole, ketoconazole, itraconazole, miconazole, voriconazole), benzodiazepines (eg, chlordiazepoxide, diazepam), capecitabine, chloramphenicol, disulfiram, estrogens, fluorouracil, fluoxetine, fluvastatin, fluvoxamine, halothane, H2-blockers (eg, cimetidine), isoniazid, methylphenidate, omeprazole, phenothiazines, salicylates, sertraline, succinamides (eg, ethosuximide), sulfonamides, ticlopidine, tolbutamide, trazodone, warfarin. Antagonized by anticancer drugs (eg, bleomycin, carboplatin, cisplatin, doxorubicin, methotrexate), chronic alcohol ingestion, carbamazepine, diazepam, folic acid, fosamprenavir, nelfinavir, reserpine, rifampin, ritonavir, St. John’s wort, sucralfate, theophylline, vigabatrin. Antagonizes anticoagulants (eg, apixaban, dabigatran, edoxaban, rivaroxaban), antiepileptic agents (eg, carbamazepine, felbamate, lacosamide, lamotrigine, topiramate, oxcarbazepine), atorvastatin, fluvastatin, simvastatin, ticagrelor, antivirals (eg, efavirenz, lopinavir/ritonavir, indinavir, nelfinavir, ritonavir, saquinavir), albendazole, chlorpropamide, clozapine, cyclosporine, digoxin, disopyramide, folic acid, methadone, mexiletine, nifedipine, nimodipine, nisoldipine, praziquantel, quetiapine, verapamil. Reduces efficacy of concomitant azoles, corticosteroids, doxycycline, estrogens, furosemide, irinotecan, oral contraceptives, paclitaxel, paroxetine, quinidine, rifampin, sertraline, teniposide, theophylline, vitamin D, warfarin. Concomitant fosamprenavir/ritonavir may potentiate amprenavir. Concomitant neuromuscular blockers (eg, pancuronium, vecuronium, rocuronium, cisatracurium); may need higher infusion rate. Variable effects with phenobarbital, valproic acid, sodium valproate. Absorption decreased by calcium, antacids. Increased risk of hyperammonemia with concomitant valproate; monitor.

Dilantin Infatabs Adverse Reactions

Adverse Reactions

Nystagmus, ataxia, slurred speech, decreased coordination, somnolence, mental confusion, headaches, dizziness, cerebellar atrophy, nausea, vomiting, constipation, gingival hyperplasia, osteomalacia, blood dyscrasias, lymphadenopathy, cardiac effects, hepatic disease, hyperglycemia, SLE, hypertrichosis, lab test abnormality; rare: serious dermatologic reactions (eg, SJS, TEN, AGEP, DRESS), multiorgan hypersensitivity (may be fatal).

Dilantin Infatabs Clinical Trials

See Literature

Dilantin Infatabs Note

Notes

To enroll in the North American Antiepileptic Drug Pregnancy Registry call (888) 233-2334.

Dilantin Infatabs Patient Counseling

See Literature