PHENYTOIN SODIUM injection solution

Nazione: Stati Uniti

Lingua: inglese

Fonte: NLM (National Library of Medicine)

Principio attivo:

PHENYTOIN SODIUM (UNII: 4182431BJH) (PHENYTOIN - UNII:6158TKW0C5)

Commercializzato da:

Cardinal Health

INN (Nome Internazionale):

PHENYTOIN SODIUM

Composizione:

PHENYTOIN SODIUM 50 mg in 1 mL

Tipo di ricetta:

PRESCRIPTION DRUG

Stato dell'autorizzazione:

Abbreviated New Drug Application

Scheda tecnica

PHENYTOIN SODIUM- PHENYTOIN SODIUM INJECTION, SOLUTION
CARDINAL HEALTH
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PHENYTOIN SODIUM INJECTION, USP
BOXED WARNING
WARNING: CARDIOVASCULAR RISK ASSOCIATED WITH RAPID INFUSION THE
RATE OF INTRAVENOUS PHENYTOIN ADMINISTRATION SHOULD NOT EXCEED 50 MG
PER MINUTE IN ADULTS
AND 1-3 MG/KG/MIN (OR 50 MG PER MINUTE, WHICHEVER IS SLOWER) IN
PEDIATRIC PATIENTS BECAUSE
OF THE RISK OF SEVERE HYPOTENSION AND CARDIAC ARRHYTHMIAS. CAREFUL
CARDIAC MONITORING IS
NEEDED DURING AND AFTER ADMINISTERING INTRAVENOUS PHENYTOIN. ALTHOUGH
THE RISK OF
CARDIOVASCULAR TOXICITY INCREASES WITH INFUSION RATES ABOVE THE
RECOMMENDED INFUSION RATE,
THESE EVENTS HAVE ALSO BEEN REPORTED AT OR BELOW THE RECOMMENDED
INFUSION RATE.
REDUCTION IN RATE OF ADMINISTRATION OR DISCONTINUATION OF DOSING MAY
BE NEEDED (SEE
WARNINGS AND DOSAGE AND ADMINISTRATION).
DESCRIPTION
Phenytoin Sodium Injection, USP is a ready-mixed solution of phenytoin
sodium in a vehicle containing
40% propylene glycol and 10% alcohol in water for injection, adjusted
to pH 12 with sodium
hydroxide.
Phentoin sodium is related to the barbiturates in chemical structure,
but has a five-membered ring. The
chemical name is sodium 5,5-diphenyl-2, 4-imidazolidinedione
represented by the following structural
formula:
CLINICAL PHARMACOLOGY
MECHANISM OF ACTION
Phenytoin is an anticonvulsant which may be useful in the treatment of
generalized tonic-clonic status
epilepticus. The primary site of action appears to be the motor cortex
where spread of seizure activity
is inhibited. Possibly by promoting sodium efflux from neurons,
phenytoin tends to stabilize the
threshold against hyperexcitability caused by excessive stimulation or
environmental changes capable
of reducing membrane sodium gradient. This includes the reduction of
posttetanic potentiation at
synapses. Loss of posttetanic potentiation prevents cortical seizure
foci from detonating adjacent
cortical areas. Phenytoin reduces the maximal activity of brain stem
centers responsible for the tonic
phase of generalized tonic-cloni