Lacosamide

BRAND NAMES:

Vimpat – It contains the active ingredient of lacosamide. It is available in the form of tablets used to treat epilepsy.

Motpoly - It contains the active ingredients of lacosamide. It is available in the form of extended-release oral tablets used to treat partial-onset seizures.

MECHANISM OF ACTION:

The exact mechanism of action of lacosamide is not fully known, however, in vitro electrophysiological studies have shown that lacosamide selectively enhances the slow inactivation of voltage-gated sodium channels, shifting the slow inactivation curve to more hyperpolarized potentials and augmenting the maximal fraction of channels in the slow inactivated state. This results in the stabilization of hyperexcitable neuronal membranes and inhibition of repetitive neuronal firing. Lacosamide does not affect the fast component of voltage-gated sodium currents, unlike traditional sodium channel blockers.

PHARMACOKINETICS:

Absorption: Following oral administration, lacosamide is fully absorbed with a minute first-pass effect. Its nearly 100% absolute bioavailability is of high quality. Food does not affect how quickly or how much is absorbed. One to four hours is the Tmax range. Steady-state plasma concentrations are achieved after three days of twice-daily repeated administration.

Distribution: The volume of distribution of lacosamide is approximately 0.6L/Kg.

Metabolism: Lacosamide is metabolized by CYP3A4, CYP2C9, and CYP2C19 to form O-desmethyl lacosamide which is a major pharmacologically inactive metabolite in humans. There is no enantiomeric interconversion of lacosamide.

Excretion: Renal excretion and biotransformation are the main ways removed from the systemic circulation. Following the intravenous and oral administration of 100 mg of radiolabelled lacosamide, less than 0.5% of the radioactivity was found in the feces and about 95% in the urine.

PHARMACODYNAMICS:

By blocking sensory neuronal voltage-gated sodium channels that mediate neuropathic pain responses, lacosamide was shown to possess analgesic activity. Lacosamide is a chiral functionalized amino acid. The S-stereoisomer does not exhibit antiepileptic activity.

DOSAGE AND ADMINISTRATION:

 Locasamide is available as tablets, capsules, and injections.

• Injections (200 mg/20 ml) are available.
• Oral tablet strengths include 50 mg, 100 mg, 150 mg, and 200 mg.
• Available in capsules of 100 mg, 150 mg, and 200 mg, as well as an oral solution of 10 mg.

Lacosamide is available in two forms: tablets and an oral solution. It is typically taken twice per day, with or without food. Take lacosamide at roughly the same times each day. Swallow the tablets whole; don't chew, split, or crush them. If you're taking the oral solution, use a dose-measuring spoon or an oral syringe to get the exact amount of liquid for each dose. Do not take more or less of it, or take it more frequently as prescribed by a physician. 

DRUG INTERACTIONS:

• Beta-blockers -used to reduce blood pressure and for certain other heart conditions
• Calcium channel blocker - is used to reduce blood pressure and certain other heart conditions.
• An antiarrhythmic -control heart rate or rhythm
• Other medicines to control seizures

CONTRAINDICATIONS:

Most medications are contraindicated if you have a history of hypersensitivity or an allergic reaction to them. Other contraindications exist, but they are more drug-specific, such as liver failure, certain blood diseases, narrow-angle glaucoma, and familial short QT syndrome, to name a few. Valproic acid and felbamate have been linked to hepatotoxicity and are thus contraindicated in hepatic failure patients. Many others are metabolized by the liver, so dosage adjustments are required at the start of treatment.

SIDE EFFECTS:

Lacosamide may cause side effects

•  Nausea 

•  Vomiting

•  Diarrhea

•  Blurred or double vision

•  Uncontrollable eye movements

•  Dizziness

•  Headache

•  Drowsiness

•  Weakness

•  Itching

Some serious side effects can be serious

•  Fast or pounding heartbeat

•  Shortness of breath

•  Slow heart rate

•  Chest pain

•  Fainting

•  Swelling of the face, throat, tongue, lips and eyes

•  Fever

•  Rash

•  Tiredness

•  Dark urine

OVERDOSE:

There have been fatal overdoses of lacosamide. There is no specific antidote for lacosamide overdose, so standard decontamination procedures should be followed. Symptoms of overdose include seizures and coma.

TOXICITY:

AED toxic effects are unique and are thought to be more common in first-generation AEDs.  One first-generation AED that is frequently linked to acute or chronic toxicity is carbamazepine. Supportive measures, high-flow hemodialysis, plasmapheresis, or charcoal hemoperfusion are some possible forms of treatment.

STORAGE:

Store in a closed container at a temperature of 68℉ to 77℉ (20 ℃ to 25 ℃). Temperatures can range from 59℉ to 86℉ (15 ℃ to 30℃) during shorter exposures, such as during transit.