Levetiracetam

Indications
Levetiracetam is indicated as an adjunctive therapy for:
Partial Onset Seizures
Myoclonic Seizures In Patients with Juvenile Myoclonic Epilepsy
Primary Generalized Tonic-Clonic Seizures
Levetiracetam injection is an alternative for adult patients (16 years and older) when oral administration is temporarily not feasible.

Therapeutic Class
Adjunct anti-epileptic drugs

Pharmacology
The exact mechanism of anticonvulsant effect is unknown but does not involve inhibitory and excitatory neurotransmission. Stereo-selective binding of Levetiracetam was confined to synaptic plasma membranes in the central nervous system with no binding occurring in peripheral tissue.
Studies show that levetiracetam affects intraneuronal Ca levels by partial inhibition of N-type Ca currents and by reducing the release of Ca from intraneuronal stores; facilitates GABA-ergic inhibitory transmission through displacement of negative modulators; reduces delayed rectifier K current; and/or binds to synaptic proteins which modulate neurotransmitter release.

Dosage
For tablet and oral solution-
Treatment should be initiated with a daily dose of 1000 mg/day, given as twice-daily dosing (500 mg twice daily). Additional dosing increments may be given (1000 mg/day additional every 2 weeks) to a maximum recommended daily dose of 3000 mg.
Use in Pediatric Patients-
1 Month To 6 Months To 4 Years To Adolescent with 20-40 kg body weight: Initial Daily dose 250 mg twice daily & Incremental Daily dose 750 mg twice daily
The daily dose should be increased every 2 weeks.

Injection-
Levetiracetam injection is for intravenous use only and must be diluted prior to administration. Levetiracetam injection (500 mg/5 mL) should be diluted in 100 mL of compatible diluents and administered intravenously as a 15-minute IV infusion. Product with particulate matter or discoloration should not be used.
Dosing Instructions: Preparation and Administration-
Dose 500 mg: Withdraw Volume 5 ml, Volume of Diluent 100 ml, Infusion Time 15 minutes
Dose 1000 mg: Withdraw Volume 10 ml, Volume of Diluent 100 ml, Infusion Time 15 minutes
Dose 1500 mg: Withdraw Volume 15 ml, Volume of Diluent 100 ml, Infusion Time 15 minutes
For example, to prepare a 1000 mg dose, dilute 10 ml of Levetiracetam injection in 100 ml of a compatible diluents and administer intravenously as a 15-minute infusion.

Administration
Levetiracetam can be initiated with either intravenous or oral administration. May be taken with or without food. Oral solution may be taken directly or diluted in a glass of water.

Interaction
No potential drug interaction has been reported

Side Effects
Dizziness, drowsiness, irritability, sore throat, tiredness, weakness are some common adverse effects. In rare cases severe allergic reaction may happen.

Pregnancy & Lactation
Pregnancy category C. No data on the use of Levetiracetam in breast feeding women are available. Data from animals indicate that Levetiracetam is secreted into milk.Therefore Levetiracetam is contraindicated during breast-feeding.

Precautions & Warnings
Severe allergic reactions, abnormal thoughts; dark urine; decreased coordination; extreme dizziness, drowsiness, tiredness, or weakness; fever, chills, or persistent sore throat; hallucinations; memory loss; mouth sores; muscle or neck pain; new or worsening mental problem; mood or behavior changes; new or worsening seizures; pain, itching or redness at the injection site;suicidal thoughts or attempts; unusual bruising or bleeding; vision changes; yellowing of the skin or eyes.

Use in Special Populations
Renal Impairment: ESRD patients undergoing dialysis: Loading dose of 750 mg, followed by 500-1,000 mg once daily; supplemental dose of 250-500 mg after dialysis.
CrCl ( CrCl (30-49 mL/min): Dosage 250-750 mg bid.
CrCl (50-79 mL/min): Dosage 500-1,000 mg bid.
Severe Hepatic Impairment: Reduce dose by 50%.

Overdose Effects
Symptoms: Somnolence, agitation, aggression, depressed level of consciousness, resp depression, coma.
Management: Symptomatic and supportive treatment. Empty the stomach by gastric lavage or induction of emesis. May perform haemodialysis.

Reconstitution
Intravenous: Dilute dose in 100 mL of suitable diluent (e.g. NaCl 0.9%, lactated Ringer's or dextrose 5% inj).

Storage Conditions
Store in a cool and dry place, protected from light and moisture. Keep out of the reach of children. Levetiracetam injection was found to be physically compatible and chemically stable when mixed with the following diluents and antiepileptic drugs for at least 24 hours and stored in polyvinyl chloride (PVC) bags at controlled room temperature 15-30°C