PHENYTOIN tablet, chewable

Country: United States

Language: English

Source: NLM (National Library of Medicine)

Active ingredient:

PHENYTOIN (UNII: 6158TKW0C5) (PHENYTOIN - UNII:6158TKW0C5)

Available from:

NCS HealthCare of KY, Inc dba Vangard Labs

INN (International Name):

PHENYTOIN

Composition:

PHENYTOIN 50 mg

Administration route:

ORAL

Prescription type:

PRESCRIPTION DRUG

Therapeutic indications:

Phenytoin chewable tablets are indicated for the control of generalized tonic-clonic (grand mal) and complex partial (psychomotor, temporal lobe) seizures and prevention and treatment of seizures occurring during or following neurosurgery. Phenytoin serum level determinations may be necessary for optimal dosage adjustments (see DOSAGE AND ADMINISTRATION and CLINICAL PHARMACOLOGY sections). Phenytoin chewable tablets are contraindicated in those patients with a history of hypersensitivity to phenytoin or its inactive ingredients, or other hydantoins. Coadministration of phenytoin is contraindicated with delavirdine due to potential for loss of virologic response and possible resistance to delavirdine or to the class of non-nucleoside reverse transcriptase inhibitors.

Product summary:

Phenytoin Chewable Tablets, USP are available containing 50 mg of phenytoin, USP. The 50 mg tablets are pink, round tablets debossed with M above the score and P50 below the score on one side of the tablet and blank on the other side. The tablets are peppermint flavored. They are available as follows: NDC 0615-7764-39 blistercards of 30 tablets Store at 20° to 25°C (68° to 77°F). [See USP Controlled Room Temperature.] Protect from moisture. Dispense in a tight, light-resistant container as defined in the USP using a child-resistant closure. PHARMACIST: Dispense a Medication Guide with each prescription.

Authorization status:

Abbreviated New Drug Application

Patient Information leaflet

PHENYTOIN- PHENYTOIN TABLET, CHEWABLE
NCS HealthCare of KY, Inc dba Vangard Labs
----------
MEDICATION GUIDE
PHENYTOIN CHEWABLE TABLETS, USP
(fen′ i toin)
50 mg
Read this Medication Guide before you start taking phenytoin chewable
tablets and each time you get a
refill. There may be new information. This information does not take
the place of talking to your
healthcare provider about your medical condition or treatment. If you
have any questions about phenytoin
chewable tablets, ask your healthcare provider or pharmacist.
What is the most important information I should know about phenytoin
chewable tablets?
Do not stop taking phenytoin chewable tablets without first talking to
your healthcare provider.
Stopping phenytoin chewable tablets suddenly can cause serious
problems.
Phenytoin chewable tablets can cause serious side effects including:
1. Like other antiepileptic drugs, phenytoin chewable tablets may
cause suicidal thoughts or actions in a
very small number of people, about 1 in 500.
Call a healthcare provider right away if you have any of these
symptoms, especially if they are new,
worse, or worry you:
•
•thoughts about suicide or dying
•
•attempts to commit suicide
•
•new or worse depression
•
•new or worse anxiety
•
•feeling agitated or restless
•
•panic attacks
•
•trouble sleeping (insomnia)
•
•new or worse irritability
•
•acting aggressive, being angry, or violent
•
•acting on dangerous impulses
•
•an extreme increase activity and talking (mania)
•
•other unusual changes in behavior or mood
How can I watch for early symptoms of suicidal thoughts and actions?
•
•Pay attention to any changes, especially sudden changes, in mood,
behaviors, thoughts, or
feelings.
•
•Keep all follow-up visits with your healthcare provider as
scheduled.
Call your healthcare provider between visits as needed, especially if
you are worried about symptoms.
Do not stop taking phenytoin chewable tablets without first talking to
a healthcare provider.
•
•Stopping phenyt

Summary of Product characteristics

PHENYTOIN- PHENYTOIN TABLET, CHEWABLE
NCS HEALTHCARE OF KY, INC DBA VANGARD LABS
----------
PHENYTOIN CHEWABLE TABS
NOT FOR ONCE-A-DAY DOSING
DESCRIPTION
Phenytoin is an antiepileptic drug.
Phenytoin is related to the barbiturates in chemical structure, but
has a five-membered ring. The
chemical name is 5,5-Diphenylhydantoin, having the following
structural formula:
Each phenytoin chewable tablet, USP for oral administration, contains
50 mg of phenytoin, USP. Also
contains: colloidal silicon dioxide, compressible sugar, corn starch,
D&C Red No. 30 Aluminum Lake,
magnesium stearate, peppermint flavor and talc.
CLINICAL PHARMACOLOGY
MECHANISM OF ACTION
Phenytoin is an antiepileptic drug which can be useful in the
treatment of epilepsy. 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 tonic-clonic (grand
mal) seizures.
PHARMACOKINETICS AND DRUG METABOLISM
Clinical studies using phenytoin chewable tablets have shown an
average plasma half-life of 14 hours
with a range of 7 to 29 hours. Steady-state therapeutic levels are
achieved at least 7 to 10 days (5 to 7
half-lives) after initiation of therapy with recommended doses of 300
mg/day.
When serum level determinations are necessary, they should be obtained
at least 5 to 7 half-lives after
treatment initiation, dosage change, or addition or subtraction of
another drug to the regimen so that
equilibrium or steady-state will have been achieved. Trough levels
provide information about clinically
effective serum level range and con