Loading…
TARO-PHENYTOIN is a brand name for Phenytoin, supplied as a suspension. The medicine, its uses, side effects and dosage are the same regardless of brand.
Used for: Taro-Phenytoin (Phenytoin Oral Suspension) is indicated for: the control of generalized tonic-clonic (grand mal) and complex partial (psychomotor, temporal lobe) seizures. Phenytoin is not effective for absence (petit mal) seizures, and not indicated for seizures due to hypoglycemic or other metabolic causes. 1. 1…
Verbatim from this product's HC label. Tap a section to expand.
4. 1 Dosing Considerations TARO-PHENYTOIN (Phenytoin Oral Suspension) Page 5 of 39 Dosage should be individualized to provide maximum benefit. There may be wide interpatient variability in phenytoin serum levels with equivalent dosages.
Phenytoin is highly bound to plasma protein and is subject to saturable metabolism. Consequently: small dose increases may substantially raise serum phenytoin concentration (and risk of toxicity), when levels are already in or above the upper therapeutic range; and phenytoin is subject to many drug interactions, which may increase serum concentrations.
3 Pharmacokinetics; and 9 DRUG INTERACTIONS. Serum blood level determinations may be necessary for optimal dosage adjustments. The clinically effective serum level is usually 40-80 micromol/L (10-20 mcg/mL). Serum blood level determinations are especially helpful when: drug or other interactions are suspected; treating geriatric patients; patients have renal or hepatic impairment, or hypoalbuminemia, or hyperbilirubinemia (in which case unbound phenytoin levels should be monitored).
2 Renal or Hepatic Disease. Switch carefully between sodium salt and free acid phenytoin products. Because there is approximately an 8% increase in drug content with the free acid form over that of the sodium salt, dosage adjustments may be necessary and serum phenytoin concentrations should be monitored when switching between free acid and sodium salt formulations.
The free acid form of phenytoin is used in Taro-Phenytoin. TARO-PHENYTOIN IS FOR ORAL USE, NOT PARENTERAL USE. Taro-Phenytoin should not be abruptly discontinued because of the possibility of increased seizure frequency, including status epilepticus.
See 7 WARNINGS AND PRECAUTIONS, General, Withdrawal Precipitated Seizures. 4. 2 Recommended Dose and Dosage Adjustment Taro-Phenytoin is not for once-a-day dosing. With recommended dosage, a period of 7 to 10 days may be required to achieve therapeutic TARO-PHENYTOIN (Phenytoin Oral Suspension) Page 6 of 39 blood levels with Taro-Phenytoin and changes in dosage (increase or decrease) should not be carried out at intervals shorter than 7 to 10 days.
Adults Patients who have received no previous treatment may be started on 1 teaspoonful (5 mL) of Taro-Phenytoin three 3 daily, and the dose then adjusted to suit individual requirements. With Taro-Phenytoin, an increase to 5 teaspoonfuls (25 mL) daily may be made i f necessary.
). g. fosphenytoin) are contraindicated in patients who have experienced phenytoin hypersensitivity (see 2 CONTRAINDICATIONS). , trimethadione) in these patients or immediate family members, other alternatives should be considered. See also 7 WARNINGS AND PRECAUTIONS, Skin.
Angioedema Angioedema has been reported in patients treated with phenytoin. Phenytoin should be discontinued immediately if symptoms of angioedema, such as facial, perioral, or upper airway swelling occur. Monitoring and Laboratory Tests Phenytoin serum level determinations may be necessary to achieve optimal dosage TARO-PHENYTOIN (Phenytoin Oral Suspension) Page 12 of 39 adjustments.
7 Drug-Laboratory Test Interactions. 5 Post- Market Adverse Reactions). Phenytoin and other anticonvulsants that have been shown to induce the CYP450 enzyme are thought to affect bone mineral metabolism indirectly by increasing the metabolism of Vitamin D3.
This may lead to Vitamin D deficiency and heightened risk of osteomalaci a, bone fractures, osteoporosis, hypocalcemia, and hypophosphatemia in chronically treated epileptic patients. Consideration should be given to monitoring with bone -related laboratory and radiological tests and initiating treatment plans, as appropriate.
Neurologic Central Nervous System Serum levels of phenytoin sustained above the optimal range may produce confusional states referred to as "delirium", "psychosis" or "encephalopathy", or rarely irreversible cerebellar dysfunction and/or cerebellar atrophy.
Accordingly, at the first sign of acute toxicity, serum drug level determinations are recommended. 3 Pharmacokinetics, Absorption, 7 WARNINGS AND PRECAUTIONS, General). Psychiatric Suicidal ideation and behaviour Suicidal ideation and behaviour have been reported in patients treated w ith antiepileptic agents in several indications.
, Hypersensitivity; and Skin). Patients being treated with delavirdine (a non-nucleoside reverse transcriptase inhibitor). 4 Drug-Drug Interactions. Patients who currently suffer from sick sinus syndrome, sinus bradycardia, sinoatrial block, second- and third- degree atrioventricular (A-V) block, QT interval prolongation, Adams-Stokes syndrome, or other heart rhythm disorders.
This is due to the effect of phenytoin on ventricular automaticity. See 7 WARNINGS AND PRECAUTIONS, Cardiovascular; and 5 OVERDOSAGE). 4 DOSAGE AND ADMINISTRATION 4. 1 Dosing Considerations TARO-PHENYTOIN (Phenytoin Oral Suspension) Page 5 of 39 Dosage should be individualized to provide maximum benefit.
There may be wide interpatient variability in phenytoin serum levels with equivalent dosages. Phenytoin is highly bound to plasma protein and is subject to saturable metabolism. Consequently: small dose increases may substantially raise serum phenytoin concentration (and risk of toxicity), when levels are already in or above the upper therapeutic range; and phenytoin is subject to many drug interactions, which may increase serum concentrations.
3 Pharmacokinetics; and 9 DRUG INTERACTIONS. Serum blood level determinations may be necessary for optimal dosage adjustments. The clinically effective serum level is usually 40-80 micromol/L (10-20 mcg/mL). Serum blood level determinations are especially helpful when: drug or other interactions are suspected; treating geriatric patients; patients have renal or hepatic impairment, or hypoalbuminemia, or hyperbilirubinemia (in which case unbound phenytoin levels should be monitored).
2 Renal or Hepatic Disease. Switch carefully between sodium salt and free acid phenytoin products. Because there is approximately an 8% increase in drug content with the free acid form over that of the sodium salt, dosage adjustments may be necessary and serum phenytoin concentrations should be monitored when switching between free acid and sodium salt formulations.
Taro-Phenytoin is contraindicated in: Patients who are hypersensitive to phenytoin, other hydantoins, or any ingredient in the formulation, including any non-medicinal ingredient, or component of the container. For a complete listing, see 6 DOSAGE FORMS, STRENGTHS, COMPOSTION AND PACKAGING; and 7 WARNINGS AND PRECAUTIONS, Hypersensitivity; and Skin).
Patients being treated with delavirdine (a non-nucleoside reverse transcriptase inhibitor). 4 Drug-Drug Interactions. Patients who currently suffer from sick sinus syndrome, sinus bradycardia, sinoatrial block, second- and third- degree atrioventricular (A-V) block, QT interval prolongation, Adams-Stokes syndrome, or other heart rhythm disorders.
This is due to the effect of phenytoin on ventricular automaticity. See 7 WARNINGS AND PRECAUTIONS, Cardiovascular; and 5 OVERDOSAGE).
Not medical advice. Always read the patient information leaflet and follow your prescriber or pharmacist.
Other brands of Phenytoin in Canada.
Know a brand we are missing in Canada? Suggest a brand →
Brand names are compiled from public regulatory records for active-ingredient mapping only. Drugvu is not affiliated with any manufacturer. This is not medical advice.
Pediatrics (< 18 years of age) Initially, 5 mg/kg/day of Taro-Phenytoin may be given in 2 or 3 equally divided doses, with subsequent dosage individualized to a maximum of 300 mg daily. A recommended daily maintenance dosage is usually 4 to 8 mg/kg.
Children over 6 years may require the minimum adult dose (300 mg/day). If the daily dosage cannot be divided equally, the larger dose should be given at bedtime. Geriatrics (> 65 years of age) Phenytoin clearance is decreased slightly in elderly patients.
Lower doses than the doses recommended for adults may be required when initiating treatment. 3 Pharmacokinetics, Geriatrics). Renal or Hepatic Disease In patients with renal or hepatic impairment or in those with hypoalbuminemia, plasma levels of unbound phenytoin are elevated.
Unbound phenytoin concentrations may be more useful in these patient populations. 1 Dosing Considerations; and 7 WARNINGS AND PRECAUTIONS, Hepatic/Biliary/Pancreatic and Renal) 4. 3 Missed Dose The patient/caregiver should be advised that if a dose is missed, the missed dose should be taken as soon as it is remembered.
If it is almost time for the next dose, the missed dose should not be taken. Instead, take the next scheduled dose. The patient/caregiver should be advised to not to make up for a missed dose by taking a double dose next time.
An FDA meta-analysis of randomized placebo-controlled trials, in which antiepileptic drugs were used for various indications, has shown a small increased risk of suicidal ideation and behaviour in patients treated with these drugs.
The mechanism of this risk is not known. All patients treated with antiepileptic drugs, irrespective of indication, should be monitored for signs of suicidal ideation and behaviour and appropriate treatment should be considered. Patients (and caregivers of patients) should be advised to seek medical advice should signs of suicidal ideation or behaviour emerge.
There were 43,892 patients treated in the placebo controlled clinical trials that were included in the meta-analysis. Approximately 75% of patients in these clinical trials were treated for TARO-PHENYTOIN (Phenytoin Oral Suspension) Page 13 of 39 indications other than epilepsy and, for the majority of non-epilepsy indications the treatment (antiepileptic drug or placebo) was administered as monotherapy.
, patients in both treatment arms were being treated with one or more antiepileptic drug). 24% for patients on placebo) is based largely on patients that received monotherapy treatment (antiepileptic drug or placebo) for non -epilepsy indications.
The study design does not allow an estimation of the risk of suicidal ideation and behaviour for patients with epilepsy that are taking antiepileptic drugs, due both to this population being the minority in the study, and the drug-placebo comparison in this population being confounded by the presence of adjunct antiepileptic drug treatment in both arms.
Renal In patients with renal impairment, plasma levels of unbound phenytoin are elevated. 2 Recommended Dose and Dosage Adjustment, Renal or Hepatic Disease). 1 Pregnant Women, Risks to fetus. Skin Serious Dermatological Reactions Phenytoin can cause rare, severe cutaneous adverse reactions (SCARs) such as acute generalized exanthematous pustulosis (AGEP), exfoliative dermatitis, Steven-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), and drug reaction with eosinophilia and systemic symptoms (DRESS), which can be fatal.
Although serious skin reactions may occur without warning, patients should be alert for the occurrence of rash and other symptoms of hypersensitivity syndrome (HSS)/DRESS. Hypersensitivity Syndrome / Drug Reaction with Eosinophilia and Systemic Symptoms Hypersensitivity Syndrome (HSS) or Drug rash with Eosinophilia and Systemic Symptoms (DRESS) has been reported in patients taking anticonvulsant drugs, including phenytoin.
Some of these events have been fatal or life threatening. TARO-PHENYTOIN (Phenytoin Oral Suspension) Page 14 of 39 HSS/DRESS typically, although not exclusively, presents with fever, rash, and/or lymphadenopathy, in association with other organ system involvement, such as hepatitis, nephritis, hematological abnormalities, myocarditis, […]
The free acid form of phenytoin is used in Taro-Phenytoin. TARO-PHENYTOIN IS FOR ORAL USE, NOT PARENTERAL USE. Taro-Phenytoin should not be abruptly discontinued because of the possibility of increased seizure frequency, including status epilepticus.
See 7 WARNINGS AND PRECAUTIONS, General, Withdrawal Precipitated Seizures. 4. 2 Recommended Dose and Dosage Adjustment Taro-Phenytoin is not for once-a-day dosing. With recommended dosage, a period of 7 to 10 days may be required to achieve therapeutic TARO-PHENYTOIN (Phenytoin Oral Suspension) Page 6 of 39 blood levels with Taro-Phenytoin and changes in dosage (increase or decrease) should not be carried out at intervals shorter than 7 to 10 days.
Adults Patients who have received no previous treatment may be started on 1 teaspoonful (5 mL) of Taro-Phenytoin three 3 daily, and the dose then adjusted to suit individual requirements. With Taro-Phenytoin, an increase to 5 teaspoonfuls (25 mL) daily may be made i f necessary.
Pediatrics (< 18 years of age) Initially, 5 mg/kg/day of Taro-Phenytoin may be given in 2 or 3 equally divided doses, with subsequent dosage individualized to a maximum of 300 mg daily. A recommended daily maintenance dosage is usually 4 to 8 mg/kg.
Children over 6 years may require the minimum adult dose (300 mg/day). If the daily dosage cannot be divided equally, the larger dose should be given at bedtime. Geriatrics (> 65 years of age) Phenytoin clearance is decreased slightly in elderly patients.
Lower doses than the doses recommended for adults may be required when initiating treatment. 3 Pharmacokinetics, Geriatrics). Renal or Hepatic Disease In patients with renal or hepatic impairment or in those with hypoalbuminemia, plasma levels of unbound phenytoin are elevated.
Unbound phenytoin concentrations may be more useful in these patient populations. 1 Dosing Considerations; and 7 WARNINGS AND PRECAUTIONS, Hepatic/Biliary/Pancreatic and Renal) 4. 3 Missed Dose The patient/caregiver should be advised that if a dose is missed, the missed dose should be taken as soon as it is remembered.
If it is almost time for the next dose, the missed dose should not be taken. Instead, take the next scheduled dose. The patient/caregiver should be advised to not to make up for a missed dose by taking a double dose next time. 5 OVERDOSAGE The lethal dose of phenytoin in pediatric patients is not known.
The lethal dose of phenytoin in adults is estimated to be 2 to 5 grams. The initial symptoms are nystagmus, ataxia, and dysarthria. Other signs are tremor, hyperreflexia, somnolence, drowsiness, lethargy, slurred speech, blurred vision, nausea, vomiting.
The patient may become comatose and hypotensive. Bradycardia and asystole/cardiac arrest have been reported (see 7 WARNINGS AND TARO-PHENYTOIN (Phenytoin Oral Suspension) Page 7 of 39 PRECAUTIONS, Cardiac effects). Death is due to respiratory and circulatory depression.
There are marked variations among individuals with respect to phenytoin plasma levels where toxicity may occur. Nystagmus on lateral gaze, usually appears at 80 micromol/L (20 mcg/mL), ataxia at 119 micromol/L (30 mcg/mL). Dysarthria and lethargy appear when the serum concentration is > 159 micromol/L (40 mcg/mL), but a concentration as high as 198 micromol/L (50 mcg/mL) has been reported without evidence of toxicity.
As much as 25 times the therapeutic dose has been taken to result in a serum concentration over >396 micromol/L (100 mcg/mL) with complete recovery. Irreversible cerebellar dysfunction and atrophy have been reported. Treatment and Management Treatment is nonspecific since there is no known antidote.
The adequacy of the respiratory and circulatory systems […]