Iracet250 mg

Iracet is a broad-spectrum antiepileptic drug used in the treatment of several seizure types, either alone or together with other antiseizure medicines. Indications are classified below by strength of evidence.

Established / Approved Uses

• Partial-onset (focal) seizures - as monotherapy in adults and adolescents 16 years and older, and as adjunctive (add-on) therapy in patients 1 month of age and older.
• Myoclonic seizures in patients with juvenile myoclonic epilepsy - as adjunctive therapy in patients 12 years and older.
• Primary generalized tonic-clonic seizures in patients with idiopathic generalized epilepsy - as adjunctive therapy in patients 6 years and older.

Off-Label / Commonly Used (not formally FDA-approved for these uses)

• Management of status epilepticus (as an alternative to phenytoin/fosphenytoin or valproate, per some emergency protocols), usually by IV route.
• Seizure prophylaxis in selected neurosurgical or traumatic brain injury settings.

The decision to use Iracet for a particular seizure type should be individualized by a treating physician based on seizure classification and patient factors.

Levetiracetam is available as immediate-release tablets (250 mg, 500 mg, 750 mg, 1000 mg), extended-release tablets, an oral solution (100 mg/mL), and a sterile solution for intravenous infusion (100 mg/mL) for patients temporarily unable to take oral therapy.

Iracet is a pyrrolidone-derivative antiepileptic drug (AED) chemically unrelated to older anticonvulsants. It is used to control certain types of seizures in people with epilepsy and works through a mechanism distinct from most other antiseizure drugs, binding to a synaptic vesicle protein involved in neurotransmitter release.

Antiepileptic drug (AED) / Anticonvulsant - pyrrolidone derivative class.

Mechanism of Action

The precise mechanism by which Levetiracetam exerts its antiepileptic effect is not completely understood. It binds to synaptic vesicle protein 2A (SV2A) in the brain, which is thought to modulate synaptic neurotransmitter vesicle release and contribute to its antiseizure activity. Unlike many older AEDs, it does not significantly affect voltage-gated sodium channels or GABAergic transmission.

Pharmacokinetics

• Absorption: Rapidly and almost completely absorbed after oral administration; bioavailability is approximately 100% and is not significantly affected by food.
• Distribution: Minimal plasma protein binding (<10%).
• Metabolism: Not extensively metabolized by the liver; the major metabolic pathway is enzymatic hydrolysis of the acetamide group, which does not involve cytochrome P450 enzymes.
• Elimination: Approximately 66% excreted unchanged in urine; plasma half-life is about 6-8 hours in adults with normal renal function (shorter in children, longer in renal impairment and the elderly).

Tablets and extended-release tablets should be swallowed whole with water and not crushed or chewed (for extended-release forms); may be taken with or without food. The oral solution can be measured with an appropriate dosing device. The intravenous formulation is administered as a diluted infusion over approximately 15 minutes by a healthcare professional, typically as a temporary alternative when oral intake is not possible, at the same total daily dose. If a dose is missed, it should be taken as soon as remembered unless it is nearly time for the next dose; doses should not be doubled.

Iracet has a low potential for drug interactions because it is not significantly metabolized by, nor does it inhibit or induce, cytochrome P450 hepatic enzymes. Clinically significant interactions are uncommon, but the following are noted:

• Enzyme-inducing antiepileptics (e.g., phenytoin, carbamazepine, phenobarbital): may modestly increase the clearance of Iracet, though this is usually not clinically significant enough to require routine dose adjustment.
• Probenecid: may inhibit renal tubular secretion of the main metabolite; clinical significance is minimal.
• CNS depressants (alcohol, sedatives, opioids, benzodiazepines): may add to sedation, dizziness, and impaired coordination caused by Iracet - concurrent use should be cautious.

No clinically significant interactions have been demonstrated with oral contraceptives, warfarin, digoxin, phenytoin, valproate, or other commonly co-administered drugs.

Common Side Effects

Serious but Less Common Effects

• Behavioral/psychiatric symptoms - aggression, agitation, anxiety, depression, mood changes, and rare suicidal ideation (see Precautions)
• Severe skin reactions - Stevens-Johnson syndrome, toxic epidermal necrolysis, and drug reaction with eosinophilia and systemic symptoms (DRESS)
• Anaphylaxis and angioedema
• Blood cell abnormalities - decreased white blood cell/neutrophil counts
• Coordination difficulties, unsteady gait

Patients should seek prompt medical attention for any rash, swelling, breathing difficulty, or unusual bleeding/bruising.

Iracet should be used during pregnancy only if clearly needed and if the potential benefit to the mother justifies the potential risk to the fetus - this decision should always be made in consultation with a physician. Animal reproduction studies have shown adverse fetal effects at doses relevant to human use, and adequate, well-controlled human studies are limited. However, published pregnancy registry and cohort data on more than a thousand first-trimester exposures with Iracet monotherapy have not shown a substantially increased risk of major birth defects compared with the general population, and it is among the more commonly used antiepileptic drugs during pregnancy - though a teratogenic risk cannot be completely excluded. Uncontrolled seizures during pregnancy also carry risks to mother and fetus, so antiepileptic therapy is generally not stopped without medical advice. Plasma levels of Iracet may decrease during pregnancy, and dose/monitoring adjustments may be needed by the treating physician.

Iracet is excreted into breast milk. A decision on breastfeeding should weigh the benefits of breastfeeding against the infant's potential drug exposure, and should be made with a physician, with the infant monitored for sedation or feeding difficulties if breastfeeding while using Iracet.

• Do not stop abruptly: Iracet must be withdrawn gradually under medical supervision, as abrupt discontinuation can increase seizure frequency and precipitate status epilepticus.
• Behavioral and psychiatric symptoms: Irritability, aggression, agitation, anxiety, depression, and psychotic symptoms have been reported, more frequently in children. Caregivers and patients should be counseled to watch for and promptly report new or worsening mood or behavior changes.
• Suicidal thoughts/behavior: As with antiepileptic drugs as a class, Iracet may increase the risk of suicidal thoughts or behavior. Patients and caregivers should be alert for depression, mood changes, or emergence of suicidal thoughts, particularly early in treatment.
• Somnolence and coordination difficulties: May impair mental alertness or motor coordination; patients should avoid driving or operating hazardous machinery until they know how Iracet affects them.
• Hematologic effects: Decreases in white blood cell counts have occurred; periodic monitoring may be advised in at-risk patients.
• Renal impairment: Dose reduction is required, since Iracet is primarily eliminated by the kidneys (see Dosage and Administration).
• Serious skin/hypersensitivity reactions: Discontinue immediately and seek medical care if rash, blistering, mucosal lesions, or signs of anaphylaxis occur.

Symptoms of Iracet overdose may include drowsiness, agitation, aggression, reduced level of consciousness, respiratory depression, and coma. There is no specific antidote. If an overdose is suspected, seek immediate medical attention or contact emergency services/poison control right away. Treatment is supportive; standard hemodialysis can remove a significant amount of the drug (approximately 50% over about 4 hours) and may be considered in severe cases, particularly with reduced kidney function.

Store at room temperature (below 30°C), away from light and moisture. Keep out of reach of children.

• Renal impairment: Dose reduction is required; see the renal dosing table in Dosage and Administration. Hemodialysis patients need a supplemental post-dialysis dose.
• Hepatic impairment: No dose adjustment is generally needed in mild-to-moderate hepatic impairment since Iracet is minimally metabolized by the liver; caution is advised in severe hepatic impairment with coexisting renal dysfunction.
• Elderly: Clearance may be reduced due to age-related decline in renal function; dose adjustment based on renal status is often needed, and elderly patients may be more sensitive to somnolence and dizziness.
• Pediatric patients: Approved from 1 month of age for adjunctive therapy of partial-onset seizures, with weight-based dosing; from 6 years for adjunctive tonic-clonic seizures; from 12 years for adjunctive myoclonic seizures and from 16 years for monotherapy of partial-onset seizures. Safety and efficacy below the approved ages/indications have not been established.

Duration of treatment with Iracet is individualized and determined by the treating physician based on seizure control, seizure type, and overall clinical course; it is often long-term. Any decision to reduce the dose or stop Iracet must be made gradually and under medical supervision, never abruptly, due to the risk of rebound seizures.

Antiepileptic drugs (AEDs); Anticonvulsants; Pyrrolidone derivatives; SV2A ligands.

Levetiracetam binds to synaptic vesicle protein 2A (SV2A) in presynaptic nerve terminals, which is believed to modulate neurotransmitter vesicle release and dampen excessive, synchronized neuronal firing that underlies seizure activity. Its exact antiepileptic mechanism is not fully established, and it differs mechanistically from most other antiseizure medicines.

Category C

Iracet is approved for adjunctive treatment of partial-onset seizures in children as young as 1 month, using weight-based dosing with gradual titration. It is approved for adjunctive treatment of primary generalized tonic-clonic seizures from age 6 and adjunctive treatment of myoclonic seizures from age 12. Behavioral side effects such as aggression, irritability, and mood changes are more common in children than adults, and caregivers should monitor closely and report any such changes. Safety and efficacy for indications or ages outside those specifically studied and approved have not been established.