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Cenobamate oral

Updated 2 Feb 2023 | Other antiepileptics


Oral formulations of cenobamate.

Drugs List

  • cenobamate 100mg tablets
  • cenobamate 12.5mg and cenobamate 25mg tablets
  • cenobamate 150mg tablets
  • cenobamate 200mg tablets
  • cenobamate 50mg tablets
  • ONTOZRY 100mg tablets
  • ONTOZRY 150mg tablets
  • ONTOZRY 200mg tablets
  • ONTOZRY 50mg tablets
  • Therapeutic Indications


    Epilepsy-partial seizures with/without secondary generalisation-adjunctive

    Cenobamate is indicated for the adjunctive treatment of focal-onset seizures with or without secondary generalisation in patients with epilepsy who have not been adequately controlled despite treatment with at least two anti-epileptic medicinal products.


    Cenobamate should always be initiated at 12.5mg once daily and titrated not faster than once every two weeks.


    Weeks 1 and 2: 12.5mg once a day.
    Weeks 3 and 4: 25mg once a day.
    Weeks 5 and 6: 50mg once a day.
    Weeks 7 and 8: 100mg once a day.
    Weeks 9 and 10: 150mg once a day.
    Week 11 and 12 and onwards: 200mg once a day.

    Target dose: 200mg once a day.

    Dose may be increased to a maximum of 400mg per day in patients who do not reach optimal seizure control. Increase by increments of 50mg/day every two weeks up to a maximum of 400mg daily.

    Patients with Renal Impairment

    Maximum recommended dose for patients with mild, moderate or severe renal impairment is 300mg/day.

    Patients with Hepatic Impairment

    A change in starting dose is not required; however, a decrease in target doses of up to 50% may be considered. Maximum recommended dose for patients with mild and moderate hepatic impairment is 200mg/day.

    Additional Dosage Information

    Missed doses
    If patient misses one dose, it is recommended that they take a single dose as soon as they remember, unless it is less than 12 hours until their next regularly scheduled dose.

    It is recommended that discontinuation of cenobamate be undertaking gradually to minimise the potential for rebound seizures, unless safety concerns require abrupt withdrawal.


    Children under 18 years
    End stage renal disease
    Severe hepatic impairment
    Shortened QT interval

    Precautions and Warnings

    Females of childbearing potential
    Glucose-galactose malabsorption syndrome
    Lactose intolerance
    Mild hepatic impairment
    Mild renal impairment

    Reduce dose in patients with renal impairment
    Advise ability to drive/operate machinery may be affected by side effects
    Contains lactose
    Monitor closely for skin reactions
    Monitor for signs of suicide ideation or behaviour
    Discontinue treatment if DRESS is suspected
    Gradually withdraw over 2 weeks
    Consider reducing dose in elderly
    Advise that effects are potentiated by CNS depressants (including alcohol)
    Female: Contraception required during and for 1 month after treatment
    Female: Non-hormonal contraception advised in addition to hormonal
    Advise patient/carers to report signs of suicide ideation or behaviour

    A dose-dependent shortening of the QTcF interval has been observed with cenobamate. Reductions of the QTcF interval below 340msec were not observed. There was no evidence from clinical trials that the combination of cenobamate with other antiepileptic medicines led to further QT-shortening. Clinicians should use caution when prescribing cenobamate in combination with other medicinal products that are known to shorten the QT.

    Drug reaction with eosinophilia and systemic symptoms (DRESS), has been reported in association with cenobamate when started at higher doses and titrated rapidly (weekly or faster titration). When initiated as 12.5mg/day and titrated every two weeks, no cases of DRESS where reported. Early manifestations of hypersensitivity, such as fever or lymphadenopathy, may be present even though rash is not evident.

    Pregnancy and Lactation


    Use cenobamate with caution during pregnancy.

    The manufacturer recommends that cenobamate should not be used during pregnancy and by women of childbearing potential not using contraception unless the clinical condition of the women requires treatment with cenobamate. At the time of writing, there is no adequate data regarding the use of cenobamate in pregnant women. Animal studies have shown that cenobamate can cross the placenta of rates. They have also shown reproductive toxicity at levels below clinical exposure.


    Cenobamate is contraindicated during breastfeeding.

    The manufacturer recommends that as a precautionary measure, breastfeeding should be discontinued during treatment with cenobamate. It is unknown if cenobamate or its metabolites are excreted in human milk. Animal studies have shown excretion of cenobamate in the maternal milk of rats. A risk to the suckling child cannot be excluded.

    LactMed (2020) indicates that if cenobamate is required by a nursing mother, it is not a reason to discontinue breastfeeding, but until more data becomes available, an alternate drug may be preferred, especially while nursing a newborn or preterm infant. Infant should be monitored for excessive drowsiness.

    Side Effects

    Blurred vision
    Drug rash with eosinophilia and systemic symptoms (DRESS)
    Dry mouth
    Gait abnormality
    Hypersensitivity reactions
    Impaired memory
    Impaired vision
    Increases in hepatic enzymes
    Movement disturbances
    Speech disturbances
    Suicidal ideation
    Suicidal tendencies


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: December 2021

    Reference Sources

    Summary of Product Characteristics: Ontozry 12.5mg tablets and 25mg film-coated tablets. Arvelle Therapeutics UK. Revised July 2021.
    Summary of Product Characteristics: Ontozry 50mg film-coated tablets. Arvelle Therapeutics UK. Revised July 2021.
    Summary of Product Characteristics: Ontozry 100mg film-coated tablets. Arvelle Therapeutics UK. Revised July 2021.
    Summary of Product Characteristics: Ontozry 150mg film-coated tablets. Arvelle Therapeutics UK. Revised July 2021.
    Summary of Product Characteristics: Ontozry 200mg film-coated tablets. Arvelle Therapeutics UK. Revised July 2021.

    NICE Evidence Services Available at: Last accessed: 20 December 2021

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available at:
    Cenobamate Last revised: 21 September 2020
    Last accessed: 21 December 2021

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