GABAPENTIN capsule

Country: United States

Language: English

Source: NLM (National Library of Medicine)

Active ingredient:

GABAPENTIN (UNII: 6CW7F3G59X) (GABAPENTIN - UNII:6CW7F3G59X)

Available from:

Major Pharmaceuticals

INN (International Name):

GABAPENTIN

Composition:

GABAPENTIN 100 mg

Prescription type:

PRESCRIPTION DRUG

Authorization status:

Abbreviated New Drug Application

Summary of Product characteristics

GABAPENTIN- GABAPENTIN CAPSULE
MAJOR PHARMACEUTICALS
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GABAPENTIN CAPSULES
RX ONLY
DESCRIPTION
Gabapentin Capsules are supplied as imprinted hard shell capsules
containing 100 mg, 300 mg, and 400
mg of gabapentin.
The inactive ingredients for the capsules are magnesium stearate,
pregelatinized starch, starch and talc.
The 100 mg capsule shell contains gelatin, sodium lauryl sulfate and
titanium dioxide. The 300 mg
capsule shell contains gelatin, sodium lauryl sulfate, titanium
dioxide, and iron oxide yellow. The 400
mg capsule shell contains gelatin, sodium lauryl sulfate, titanium
dioxide, FD&C Yellow No.6 and
FD&C Blue No.1.
Gabapentin is described as 1-(aminomethyl)cyclohexaneacetic acid with
a molecular formula of
C H NO and a molecular weight of 171.24. The structural formula of
gabapentin is:
Gabapentin is a white to off-white crystalline solid with a pK of 3.7
and a pK 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.
CLINICAL PHARMACOLOGY
MECHANISM OF ACTION
The mechanism by which gabapentin exerts its analgesic action is
unknown, but in animal models of
analgesia, gabapentin prevents allodynia (pain-related behavior in
response to a normally innocuous
stimulus) and hyperalgesia (exaggerated response to painful stimuli).
In particular, gabapentin prevents
pain-related responses in several models of neuropathic pain in rats
or mice (e.g. spinal nerve ligation
models, streptozocin-induced diabetes model, spinal cord injury model,
acute herpes zoster infection
model). Gabapentin also decreases pain-related responses after
peripheral inflammation (carrageenan
footpad test, late phase of formalin test). Gabapentin did not alter
immediate pain-related behaviors (rat
tail flick test, formalin footpad acute phase, acetic acid abdominal
constriction test, footpad heat
irradiation test). The relevance of these models to human pain is not
known.
The mechanism by which gabapentin e