Fosphenytoin


Generic Medicine Info
Contraindications
Sinus bradycardia, sino-atrial block, 2nd- or 3rd-degree AV block, Stokes-Adams syndrome; history of acute hepatotoxicity associated with fosphenytoin or phenytoin; acute intermittent porphyria. Concomitant use with delavirdine.
Special Precautions
Patients with hypotension, severe myocardial insufficiency, acute cerebrovascular event, hyperbilirubinaemia, hypoalbuminaemia, hypothyroidism, phosphate restriction, diabetes mellitus. Critically ill and debilitated patients. Patients of Asian ancestry. Patients who are positive for HLA-B*15:02 allele; CYP2C9 poor metabolisers or intermediate metabolisers with CYP2C9 activity score of 1. Not indicated for the treatment of absence seizures and seizures associated with hypoglycaemia or other metabolic causes. Avoid abrupt withdrawal. Renal and hepatic impairment. Children and elderly. Pregnancy and lactation. Patient Counselling This drug may cause dizziness and drowsiness if affected, do not drive or operate machinery. Monitoring Parameters Monitor ECG, blood pressure, heart rate, and respiratory function during and approx 30 minutes post-infusion; vital signs, CBC, LFT, plasma phenytoin concentrations; signs of suicidal ideation and behaviours.
Adverse Reactions
Significant: Suicidal ideation and behaviour, confusional states (e.g. delirium, psychosis or encephalopathy) or rarely, irreversible cerebellar dysfunction and/or atrophy; oedema, discolouration and pain at the inj site, skin necrosis and limb ischaemia; lymphadenopathy (local or generalised) including benign lymph node hyperplasia, pseudolymphoma, lymphoma and Hodgkin's disease; angioedema; transient itching, burning and/or paraesthesia in the groin during or post-infusion. Cardiac disorders: CV collapse (IV). Ear and labyrinth disorders: Tinnitus, vertigo. Eye disorders: Blurred vision, visual impairment. Gastrointestinal disorders: Dysgeusia, dry mouth, nausea, vomiting. General disorders and administration site conditions: Ataxia, asthenia. Metabolism and nutrition disorders: Hyperglycaemia. Musculoskeletal and connective tissue disorders: Chills. Nervous system disorders: Dizziness, headache, nystagmus, tremor, abnormal coordination; CNS depression (IV). Psychiatric disorders: Somnolence, euphoric mood, stupor, dysarthria. Skin and subcutaneous tissue disorders: Pruritus, ecchymosis. Vascular disorders: Hypotension, vasodilation.
Potentially Fatal: Severe CV reactions (e.g. atrial and ventricular conduction depression, hypotension, ventricular fibrillation, asystole) associated with rapid infusion, hypersensitivity syndrome or drug reaction with eosinophilia and systemic symptoms (DRESS), severe cutaneous adverse reactions (e.g. acute generalised exanthematous pustulosis, exfoliative dermatitis, Stevens-Johnson syndrome, toxic epidermal necrolysis), toxic hepatitis, acute hepatoxicity, haematopoietic complications (e.g. thrombocytopenia, leucopenia, granulocytopenia, agranulocytosis, pancytopenia).
Drug Interactions
Increased plasma levels with amiodarone, azole antifungals (e.g. fluconazole), capecitabine, chloramphenicol, disulfiram, estrogens, felbamate, fluorouracil, fluoxetine, fluvoxamine, H2-antagonists (e.g. cimetidine), halothane, isoniazid, methylphenidate, omeprazole, oxcarbazepine, salicylates, sertraline, succinimides (e.g. ethosuximide), sulfonamides (e.g. sulfamethizole), tacrolimus, ticlopidine, tolbutamide, topiramate, trazodone. Decreased plasma levels with antineoplastic drugs (e.g. bleomycin, carboplatin, doxorubicin), diazoxide, folic acid, fosamprenavir, nelfinavir, reserpine, rifampicin, ritonavir, theophylline, vigabatrin. Altered (increased or decreased) plasma levels with carbamazepine, chlordiazepoxide, ciprofloxacin, diazepam, phenobarbital, phenothiazines, valproic acid, Na valproate. May impair the efficacy of corticosteroids, doxycycline, furosemide, fluvastatin, irinotecan, oral contraceptives, glibenclamide, paclitaxel, paroxetine, quinidine, rifampicin, teniposide, theophylline, vitamin D. Increased and decreased prothrombin time or INR responses with warfarin. May decrease plasma levels of active metabolites of albendazole, certain HIV antivirals (e.g. efavirenz), atorvastatin, chlorpropamide, clozapine, ciclosporin, digoxin, methadone, mexiletine, nifedipine, nimodipine, nisoldipine, praziquantel, simvastatin, verapamil. May decrease serum levels of amprenavir (active metabolite of fosamprenavir) when given with fosamprenavir alone. May increase amprenavir concentration when given with fosamprenavir and ritonavir combination. May cause resistance to the neuromuscular blocking action of the non-depolarising neuromuscular blocking agents (e.g. pancuronium).
CIMS Class
ATC Classification
N03AB05 - fosphenytoin ; Belongs to the class of hydantoin derivatives antiepileptics.
Disclaimer: This information is independently developed by CIMS based on fosphenytoin from various references and is provided for your reference only. Therapeutic uses, prescribing information and product availability may vary between countries. Please refer to CIMS Product Monographs for specific and locally approved prescribing information. Although great effort has been made to ensure content accuracy, CIMS shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2021 CIMS. All rights reserved. Powered by CIMSAsia.com
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