April 27, 2017
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"The U.S. Food and Drug Administration today approved Aptiom (eslicarbazepine acetate) as an add-on medication to treat seizures associated with epilepsy.

Epilepsy is a brain disorder caused by abnormal or excessive activity in the brain"...



Side Effects


Clinically significant adverse reactions that appear in other sections of the labeling include the following:

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

During its development for the adjunctive treatment of seizures associated with LGS, ONFI was administered to 333 healthy volunteers and 300 patients with a current or prior diagnosis of LGS, including 197 patients treated for 12 months or more. The conditions and duration of exposure varied greatly and included single- and multipledose clinical pharmacology studies in healthy volunteers and two double-blind studies in patients with LGS (Study 1 and 2) [see Clinical Studies]. Only Study 1 included a placebo group, allowing comparison of adverse reaction rates on ONFI at several doses to placebo.

Adverse Reactions Leading To Discontinuation In An LGS Placebo Controlled Clinical Trial (Study 1)

The adverse reactions associated with ONFI treatment discontinuation in ≥1% of patients in decreasing order of frequency included lethargy, somnolence, ataxia, aggression, fatigue, and insomnia.

Most Common Adverse Reactions In An LGS Placebo Controlled Clinical Trial (Study 1)

Table 3 lists the adverse reactions that occurred in ≥5% of ONFI-treated patients (at any dose), and at a rate greater than placebo-treated patients, in the randomized, doubleblind, placebo-controlled, parallel group clinical study of adjunctive AED therapy for 15 weeks (Study 1).

Table 3. Adverse Reactions Reported for ≥5% of Patients and More Frequently than Placebo in Any Treatment Group

ONFI Dose Level All ONFI
Gastrointestinal Disorders
  Vomiting 5 9 5 7 7
  Constipation 0 2 2 10 5
  Dysphagia 0 0 0 5 2
General Disorders and Administration Site Conditions
  Pyrexia 3 17 10 12 13
  Irritability 5 3 11 5 7
  Fatigue 2 5 5 3 5
Infections and Infestations
  Upper respiratory tract infection 10 10 13 14 12
  Pneumonia 2 3 3 7 4
  Urinary tract infection 0 2 5 5 4
  Bronchitis 0 2 0 5 2
Metabolism and Nutrition Disorders
  Decreased appetite 3 3 0 7 3
  Increased appetite 0 2 3 5 3
Nervous System Disorders
  Somnolence or Sedation 15 17 27 32 26
    Somnolence 12 16 24 25 22
    Sedation 3 2 3 9 5
  Lethargy 5 10 5 15 10
  Drooling 3 0 13 14 9
  Ataxia 3 3 2 10 5
  Psychomotor hyperactivity 3 3 3 5 4
  Dysarthria 0 2 2 5 3
Psychiatric Disorders
  Aggression 5 3 8 14 8
  Insomnia 2 2 5 7 5
Respiratory Disorders
  Cough 0 3 5 7 5
aMaximum daily dose of 5 mg for ≤30 kg body weight; 10 mg for >30 kg body weight
bMaximum daily dose of 10 mg for ≤30 kg body weight; 20 mg for >30 kg body weight
cMaximum daily dose of 20 mg for ≤30 kg body weight; 40 mg for >30 kg body weight

Post Marketing Experience

These reactions are reported voluntarily from a population of uncertain size; therefore, it is not possible to estimate their frequency or establish a causal relationship to drug exposure. Adverse reactions are categorized by system organ class.

Blood Disorders: Anemia, eosinophilia, leukopenia, thrombocytopenia

Eye Disorders: Diplopia, vision blurred

Gastrointestinal Disorders: Abdominal distention

General Disorders and Administration Site Conditions: Hypothermia

Investigations: Hepatic enzyme increased

Musculoskeletal: Muscle spasms

Psychiatric Disorders: Agitation, anxiety, apathy, confusional state, depression, delirium, delusion, hallucination

Renal and Urinary Disorders: Urinary retention

Respiratory Disorders: Aspiration, respiratory depression

Skin and Subcutaneous Tissue Disorders: Rash, urticaria, angioedema, and facial and lip edema

Read the Onfi (clobazam tablets and oral suspension) Side Effects Center for a complete guide to possible side effects



The concomitant use of benzodiazepines and opioids increases the risk of respiratory depression because of actions at different receptor sites in the CNS that control respiration. Benzodiazepines interact at GABAA sites, and opioids interact primarily at mu receptors. When benzodiazepines and opioids are combined, the potential for benzodiazepines to significantly worsen opioid-related respiratory depression exists. Limit dosage and duration of concomitant use of benzodiazepines and opioids, and follow patients closely for respiratory depression and sedation [see WARNINGS AND PRECAUTIONS].

CNS Depressants And Alcohol

Concomitant use of ONFI with other CNS depressants may increase the risk of sedation and somnolence [see WARNINGS AND PRECAUTIONS].

Alcohol, as a CNS depressant, will interact with ONFI in a similar way and also increases clobazam’s maximum plasma exposure by approximately 50%. Therefore, caution patients or their caregivers against simultaneous use with other CNS depressant drugs or alcohol, and caution that the effects of other CNS depressant drugs or alcohol may be potentiated [see WARNINGS AND PRECAUTIONS].

Effect Of ONFI On Other Drugs

Hormonal Contraceptives

ONFI is a weak CYP3A4 inducer. As some hormonal contraceptives are metabolized by CYP3A4, their effectiveness may be diminished when given with ONFI. Additional non- hormonal forms of contraception are recommended when using ONFI [see CLINICAL PHARMACOLOGY, PATIENT INFORMATION].

Drugs Metabolized By CYP2D6

ONFI inhibits CYP2D6. Dose adjustment of drugs metabolized by CYP2D6 may be necessary [see CLINICAL PHARMACOLOGY].

Effect Of Other Drugs On ONFI

Strong And Moderate Inhibitors Of CYP2C19

Strong and moderate inhibitors of CYP2C19 may result in increased exposure to N-desmethylclobazam, the active metabolite of clobazam. This may increase the risk of dose-related adverse reactions. Dosage adjustment of ONFI may be necessary when co-administered with strong CYP2C19 inhibitors (e.g., fluconazole, fluvoxamine, ticlopidine) or moderate CYP2C19 inhibitors (e.g., omeprazole) [see CLINICAL PHARMACOLOGY].

Drug Abuse And Dependence

Controlled Substance

ONFI contains clobazam which is a Schedule IV controlled substance.


ONFI can be abused in a similar manner as other benzodiazepines, such as diazepam.

The pharmacological profile of ONFI is similar to that of other benzodiazepines listed in Schedule IV of the Controlled Substance Act, particularly in its potentiation of GABAergic transmission through its action on GABAA receptors, which leads to sedation and somnolence.

The World Health Organization epidemiology database contains reports of drug abuse, misuse, and overdoses associated with clobazam.

Drug abuse is the intentional non-therapeutic use of a drug, repeatedly or even sporadically, for its rewarding psychological or physiological effects.



Physical dependence is a state of adaptation that is manifested by a specific withdrawal syndrome that can be produced by abrupt cessation, rapid dose reduction, decreasing blood levels of the drug, and/or administration of an antagonist. In clinical trials, cases of dependency were reported following abrupt discontinuation of ONFI.

The risk of dependence is present even with use of ONFI at the recommended dose range over periods of only a few weeks. The risk of dependence increases with increasing dose and duration of treatment. The risk of dependence is increased in patients with a history of alcohol or drug abuse.


Abrupt discontinuation of ONFI causes withdrawal symptoms. As with other benzodiazepines, ONFI should be withdrawn gradually [see DOSAGE AND ADMINISTRATION, WARNINGS AND PRECAUTIONS].

In ONFI clinical pharmacology trials in healthy volunteers, the most common withdrawal symptoms after abrupt discontinuation were headache, tremor, insomnia, anxiety, irritability, drug withdrawal syndrome, palpitations, and diarrhea [see WARNINGS AND PRECAUTIONS].

Other withdrawal reactions to clobazam reported in the literature include restlessness, panic attacks, profuse sweating, difficulty in concentrating, nausea and dry retching, weight loss, blurred vision, photophobia, and muscle pain and stiffness. In general, benzodiazepine withdrawal may cause seizures, psychosis, and hallucinations [see WARNINGS AND PRECAUTIONS].

Read the Onfi Drug Interactions Center for a complete guide to possible interactions

This monograph has been modified to include the generic and brand name in many instances.

Last reviewed on RxList: 1/3/2017

Side Effects

Report Problems to the Food and Drug Administration


You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.


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