Gabapentin May Cause Serious or Life-Threatening Allergic Reactions

Gabapentin may cause serious or life-threatening allergic reactions that may affect your skin or other parts of your body such as your liver or blood cells. This may cause you to be hospitalized or to stop NEURONTIN.

Gabapentin 800 mg Tab-IVA
Gabapentin 800 mg Tab-IVA

You may or may not have a rash with an allergic reaction caused by NEURONTIN. Call a healthcare provider right away if you have any of the following symptoms:

      • skin rash
      • hives
      • difficulty breathing
      • fever
      • swollen glands that do not go away
      • swelling of your face, lips, throat, or tongue
      • yellowing of your skin or of the whites of the eyes
      • unusual bruising or bleeding
      • severe fatigue or weakness
      • unexpected muscle pain
      • frequent infections

These symptoms may be the first signs of a serious reaction. A healthcare provider should examine you to decide if you should continue taking NEURONTIN.

How does Gabapentin Work ?

Gabapentin is a medicine that may be used for the treatment of certain seizure disorders or nerve pain.

Neurontin (gabapentin) is an anti-epileptic medication used to treat seizures. Neurontin is used alone or in combination with other medications to treat seizures caused by epilepsy in adults and children who are at least 12 years old. Neurontin is also used to treat nerve pain caused by shingles (herpes zoster).

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 C9H17NO2 and the molecular weight is 171.24. The structural formula of gabapentin is:

NEURONTIN® (gabapentin) - Structural Formula Illustration

Gabapentin is a white to off-white crystalline solid with a pKa1 of 3.7 and a pKa2 of 10.7. It is freely soluble in water and both basic and acidic aqueous solutions. The log of the partition coefficient (noctanol/ 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: lactose, cornstarch, talc, gelatin, titanium dioxide, FD&C Blue No. 2, yellow iron oxide (300 mg and 400 mg only), and red iron oxide (400 mg only).

Each Neurontin tablet contains 600 mg or 800 mg of gabapentin and the following inactive ingredients: poloxamer 407, copovidone, cornstarch, magnesium stearate, hydroxypropyl cellulose, talc, and candelilla wax

Neurontin oral solution contains 250 mg of gabapentin per 5 mL (50 mg per mL) and the following inactive ingredients: glycerin, xylitol, purified water, and artificial cool strawberry anise flavor.

How gabapentin works
How gabapentin works

Experts aren’t sure exactly how gabapentin works, but research has shown that gabapentin binds strongly to a specific site (called the alpha2-delta site) on voltage-gated calcium channels. This action is thought to be the mechanism for its nerve-pain relieving and anti-seizure properties.

Gabapentin  (brand name Horizant) is a prodrug of gabapentin which has been designed to overcome the limitations of gabapentin, such as poor absorption and a short duration of action. Gabapentin enacarbil is effective for restless legs syndrome (RLS) and postherpetic neuralgia (nerve pain that occurs following Shingles).

Gabapentin belongs to the group of medicines known as anticonvulsants.