April 27, 2017
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"June 8, 2012 -- The FDA has approved a drug currently used for restless leg syndrome to treat a common and painful complication of shingles, according to the medication's manufacturers.

Horizant (gabapentin enacarbil) has been approve"...



(gabapentin enacarbil) Extended-Release Tablets


HORIZANT (gabapentin enacarbil) is a prodrug of gabapentin. Gabapentin enacarbil is described as (1-{[({(1RS)-1-[(2-Methylpropanoyl)oxy]ethoxy}carbonyl)amino]methyl} cyclohexyl) acetic acid. It has a molecular formula of C16H27NO6 and a molecular weight of 329.39. It is a racemate and has the following structural formula:

HORIZANT (gabapentin enacarbil) Structural Formula Illustration

Gabapentin enacarbil is a white to off-white crystalline solid with a melting onset of approximately 64°C and a solubility of 0.5 mg/mL in water and 10.2 mg/mL in phosphate buffer (pH 6.3).

HORIZANT is administered orally. Each HORIZANT Extended-Release Tablet contains 300 mg or 600 mg of gabapentin enacarbil and the following inactive ingredients: colloidal silicon dioxide, dibasic calcium phosphate dihydrate, glyceryl behenate, magnesium stearate, sodium lauryl sulfate, and talc.

What are the precautions when taking gabapentin enacarbil extended-release tablets (Horizant)?

Before taking gabapentin enacarbil, tell your doctor or pharmacist if you are allergic to it; or to gabapentin; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: kidney disease, mental/mood problems (such as depression, thoughts of suicide), use/abuse of drugs/alcohol.

This drug may make you dizzy or drowsy or cause blurred vision. Do not drive, use machinery, or do any activity that requires alertness or clear vision until you are sure you can perform such activities safely. Avoid alcoholic beverages.

Before having surgery, tell your doctor...

Read All Potential Precautions of Horizant »

Last reviewed on RxList: 4/25/2016
This monograph has been modified to include the generic and brand name in many instances.

Horizant - User Reviews

Horizant User Reviews

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