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    DEA Class;  Rx

    Common Brand Names; Neurontin, Gralise

    • GABA Analogs

    Parenteral prodrug of phenytoin; hydantoin anticonvulsant
    Used for status epilepticus, seizures during neurosurgery, and as a short-term substitution for oral phenytoin
    May cause transient, infusion-related, paresthesias and pruritus; systemic adverse reactions identical to phenytoin

    Indicated for the adjunctive treatment of partial seizures with or without secondary generalized tonic-clonic seizures.

    For the treatment of moderate to severe primary restless legs syndrome (RLS).
    For the treatment of amyotrophic lateral sclerosis (ALS).
    For the treatment of tremor.
    For the treatment of paroxysmal symptoms and spasticity due to multiple sclerosis.
    For the treatment of hot flashes due to menopause or in women who have been treated for breast cancer.
    For the treatment of pruritus, including chronic kidney disease-associated pruritus (CKD-aP).
    For the treatment of neuropathic pain, including postherpetic neuralgia (PHN), diabetic neuropathy, and trigeminal neuralgia.


    • Diplopia (6-10%)
    • Nystagmus (6-10%)
    • Tremor (6-10%)
    • Amblyopia (1-5%)
    • Back pain (1-5%)
    • Constipation (1-5%)
    • Depression (1-5%)
    • Dry mouth (1-5%)
    • Dysarthria (1-5%)
    • Dyspepsia (1-5%)
    • Hostility (5-8% children)
    • Hyperkinesia (3-5%)
    • Increased appetite (1-5%)
    • Leukopenia (1-5%)
    • Myalgia (1-5%)
    • Nervousness (1-5%)
    • Peripheral edema (1-5%)
    • Pharyngitis (1-5%)
    • Pruritus (1-5%)
    • Rhinitis (1-5%)
    • Vasodilation (1-5%)
    • Weight gain (1-5%)
    • Abnormal vision (>1%)
    • Anorexia (>1%)
    • Arthralgia (>1%)
    • Asthenia (>1%)
    • HTN (>1%)
    • Malaise (>1%)
    • Paresthesia (>1%)
    • Purpura (>1%)
    • Vertigo (>1%)
    • Angioedema
    • Blood glucose fluctuation
    • Breast enlargement
    • Erythema multiforme
    • Elevated liver function tests
    • Fever
    • Hyponatremia
    • Jaundice
    • Stevens-Johnson syndrome
    • Adverse events following abrupt discontinuation have also been reported; the most frequently reported events have been anxiety, insomnia, nausea, pain, and sweating

    Increased blood CPK levels and rhabdomyolysis reported

    Antiepileptic drugs increase risk of suicidal thoughts or behavior in patients taking these drugs for any indication; monitor for emergence or worsening depression, suicidal thoughts or behavior, and/or any unusual changes in mood or behavior

    Anaphylaxis and angioedema reported after first dose or at any time during treatment; instruct patients to discontinue therapy and seek medical care should they experience signs or symptoms of anaphylaxis or angioedema

    May cause CNS depression, which may impair ability to operate heavy machinery; advise patients not to drive until they have gained enough experience to assess whether therapy will impair ability to drive

    Extended release formulation (Garlise) not studied in the treatment of seizures

    Extended release formulation (Garlise), not interchangeable with immediate release

    May potentiate effects of other sedatives or ethanol when administered concomitantly

    Do not discontinue abruptly (may increase seizure frequency); gradually taper over a minimum of 1 week

    Ages 3-12 years: Risk of neuropsychiatric adverse events, including emotional lability, hostility, thought disorders, and hyperkinesia

    There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to antiepileptic drugs (AEDs) during pregnancy

    Gabapentin is secreted in human milk following oral administration; effects on breastfed infant and on milk production are unknown; developmental and health benefits of breastfeeding should be considered along with mother’s clinical need for therapy and any potential adverse effects on breastfed infant from treatment or from underlying maternal condition


    3600 mg/day PO (immediate-release products, e.g., Neurontin); 1800 mg/day PO (extended-release tablets; Gralise ONLY); 1200 mg/day PO (extended-release tablets; Horizant ONLY).


    3600 mg/day PO (immediate-release products, e.g., Neurontin); 1800 mg/day PO (extended-release tablets; Gralise ONLY); 1200 mg/day PO (extended-release tablets; Horizant ONLY).


    3600 mg/day PO (immediate-release products, e.g., Neurontin); safety and efficacy of extended-release gabapentin products have not been established.


    3—12 years: 50 mg/kg/day PO immediate-release products has been suggested, higher dosages occasionally used in refractory patients. Safety and efficacy of extended-release gabapentin products have not been established.
    < 3 years: Safety and efficacy have not been established.


    Safety and efficacy have not been established.


    Safety and efficacy have not been established.



    • 100mg
    • 300mg
    • 400mg


    • 300mg (Gralise)
    • 600mg (Gralise, Neurontin)
    • 800mg (Neurontin)

    oral solution

    • 250mg/5mL