Drug Index

Lamotrigine

 
print

Mechanism :

The precise mechanism by which lamotrigine exerts its anticonvulsant action are unknown. In animal models it was effective in preventing seizure spread in the maximum electroshock (MES) and pentylenetetrazol (scMet) tests and prevented seizures in the visually and electrically evoked after-discharge (EEAD) tests for antiepileptic activity.


Indication :

• Tonic clonic seizures

• Absence seizures

• Atonic seizures

• Myoclonic seizures

• Partial seizures


Contraindications :

Lamotrigine is contraindicated in patients who have demonstrated hypersensitivity to the drug or its ingredients.

Use with caution in renal failure, do not withdraw abruptly, reduce initial doses in liver disease and titrate to response.


Dosing :

Oral: 2-12 years: 0.6 mg/kg/24 hours in 1-2 doses for 2 weeks, then 1.2 mg/kg/24 hours for 2 weeks, then 5-15 mg/kg/24 hours according to response. Max: 400 mg/24 hours.

>12 years: 100-400 mg/day in 1-2 divided doses. Start with 25 mg alternate day for 2 weeks, then 25 mg daily for 2 weeks and then increase by 25-50 mg/day every 1-2 weeks. Max: 400 mg/day.

On valproate:

If the child is on valproate: 0.15 mg/kg/24 hours in 1-2 doses for 2 weeks, then 0.3 mg/kg/24 hours for 2 weeks, then 1-5 mg/kg/24 hours according to response, Max: 200 mg/24 hours.

>12 years: 50-200 mg/day in 1-2 divided doses. Start with 25 mg alternate day for 2 weeks, then 25 mg daily for 2 weeks and then increase by 25-50 mg/day every 1-2 weeks. Max: 200 mg/day.


Adverse Effect :

Measles-like skin rash, usually within first 8 weeks of commencing therapy, rarely Stevens-Johnson syndrome, nausea/vomiting, headache, dizziness, somnolence, diplopia and blurred vision, fever and ataxia.


Interaction :

Oral Contraceptives: Increased the apparent clearance of lamotrigine.
Folate Inhibitors: Lamotrigine is a weak inhibitor of dihydrofolate reductase. Prescribers should be aware of this action when prescribing other medications that inhibit folate metabolism.
Phenobarbital, Primidone: The addition of phenobarbital or primidone decreases lamotrigine steady-state concentrations by approximately 40%.
Sodium valproate: May be synergistic in absence (typical and atypical), tonic-clonic and myoclonic seizures.
Ethosuximide: May be synergistic in absence (typical and atypical) seizures.
Carbamazepine: Lamotrigine may increase the risk of adverse effects.


07/15/2019 05:45:42 Lamotrigine
ask a doctor
Ask a Doctor
Disclaimer: The information given by www.pediatriconcall.com is provided by medical and paramedical & Health providers voluntarily for display & is meant only for informational purpose. The site does not guarantee the accuracy or authenticity of the information. Use of any information is solely at the user's own risk. The appearance of advertisement or product information in the various section in the website does not constitute an endorsement or approval by Pediatric Oncall of the quality or value of the said product or of claims made by its manufacturer.
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0