GRALISE
Manufacturer:
Depomed, Inc.
Active Ingredient(s):
Gabapentin 300mg, 600mg; tabs.
Indication(s):
Postherpetic neuralgia.
Pharmacology:
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 normally innocuous stimulus) and hyperalgesia (exaggerated response to painful stimuli). Gabapentin is structurally related to the neurotransmitter gamma-aminobutyric acid (GABA) but has no effect on GABA binding, uptake, or degradation. In vitro studies have shown that gabapentin binds with high affinity to the α2δ subunit of voltage-activated calcium channels; however, the relationship of this binding to the effects of gabapentin remain to be elucidated. It is hypothesized that gabapentin antagonizes thrombospondin binding to α2δ-1 as a receptor involved in excitatory synapse formation and suggested that gabapentin may function therapeutically by blocking new synapse formation.
Clinical Trials:
The efficacy of Gralise in the management of postherpetic neuralgia was demonstrated in a double-blind, placebo-controlled, multicenter study. This study enrolled patients with postherpetic neuralgia persisting for at least 6 months following healing of herpes zoster rash and a minimum baseline pain intensity score of at least 4 on an 11-point numerical pain rating scale ranging from 0 (no pain) to 10 (worst possible pain).
This 11-week study compared Gralise 1800mg once daily with placebo. A total of 221 and 231 patients were treated with Gralise or placebo, respectively. The study treatment including titration for all patients comprised a 10-week treatment period followed by 1-week of dose tapering. Double-blind treatment began with titration starting at 300mg/day and titrated up to a total daily dose of 1800mg over 2 weeks, followed by 8 weeks fixed dosing at 1800mg once daily, and then 1 week of dose tapering. During the 8-week stable dosing period, patients took 3 active or placebo tablets each night with the evening meal. During baseline and treatment, patients recorded their pain in a daily diary using an 11-point numeric pain rating scale. The mean baseline pain score was 6.6 and 6.5 for Gralise and placebo-treated patients, respectively. At study endpoint, treatment with Gralise statistically significantly improved the mean pain score from baseline.
Legal Classification:
Rx
Adults:
Swallow whole; do not crush, split or chew tabs. Take once daily with the evening meal. ≥18 years: initially 300mg on Day 1, 600mg on Day 2, 900mg on Days 3–6, 1200mg on Days 7–10, 1500mg on Days 11–14, titrate up to 1800mg on Day 15. Renal impairment: CrCl 30–60mL/min: 600–1800mg. CrCl <30mL/min or on hemodialysis: not recommended.
Children:
<18 years: not recommended.
Warnings/Precautions:
Not interchangeable with other gabapentin products. Epilepsy. Increased risk of suicidal thoughts/behavior. Monitor for worsening of depression, suicidal thoughts/behavior, and unusual changes in mood/behavior. Renal impairment. Avoid abrupt cessation; if discontinuing, withdraw gradually over 1 week or longer. Elderly. Pregnancy (Cat. C). Nursing mothers: not recommended.
Interaction(s):
May affect or be affected by hydrocodone. Potentiated by morphine. Separate dosing of aluminum- or magnesium-containing antacids by at least 2 hours. May cause false (+) results with urine protein tests (eg, Multistix SG).
Adverse Reaction(s):
Dizziness, somnolence, headache, lethargy, peripheral edema, diarrhea, dry mouth, pain in extremity.
How Supplied:
Tabs 300mg—30
600mg—90
30-Day Starter pack—78 (9 x 300mg + 69 x 600mg)
Last Updated:
9/29/2011
