SPL Set ID: 97935fd9-1d4a-43b6-a5d9-de994591187b

The active ingredient in NEURONTIN capsules, tablets, and oral solution is gabapentin, which has the chemical name 1-(aminomethyl)cyclohexaneacetic acid. The molecular formula of gabapentin is C 9 H 17 NO 2 and the molecular weight is 171.24. The structural formula of gabapentin is: Gabapentin is a white to off-white crystalline solid with a pK a1 of 3.7 and a pK a2 of 10.7. It is freely soluble in water and both basic and acidic aqueous solutions. The log of the partition coefficient (n-octanol/0.05M phosphate buffer) at pH 7.4 is -1.25. Each NEURONTIN capsule contains 100 mg, 300 mg, or 400 mg of gabapentin and the following inactive ingredients: cornstarch, FD&C Blue No. 2, gelatin, lactose, red iron oxide (400 mg only), talc, titanium dioxide, and yellow iron oxide (300 mg and 400 mg only). Each NEURONTIN tablet contains 600 mg or 800 mg of gabapentin and the following inactive ingredients: candelilla wax, copovidone, cornstarch, hydroxypropyl cellulose, magnesium stearate, poloxamer 407, and talc. NEURONTIN oral solution contains 250 mg of gabapentin per 5 mL (50 mg per mL) and the following inactive ingredients: artificial cool strawberry anise flavor, glycerin, purified water, and xylitol. structural formula of gabapentin