How does clobazam work?
Clobazam is an active substance from the benzodiazepine group. These substances increase the affinity of the body’s own neurotransmitter GABA (gamma-aminobutyric acid) to its binding site on the GABAA receptor.
In the presence of clobazam, the GABA effect on the receptor increases. More chloride ions flow into the nerve cell, making it less excitable. In this way, the drug increases the calming, anti-anxiety and anticonvulsant effect of GABA.
When is clobazam used?
Clobazam is approved for the following indications:
- for the symptomatic treatment of acute and chronic states of tension, agitation and anxiety in adults (Germany, Austria, Switzerland) and in children and adolescents (Switzerland only)
- for adjunctive therapy in adults and children aged two years and older with epileptic seizures who are not seizure-free with standard treatment
What are the side effects of clobazam?
Typical side effects of clobazam are tiredness, drowsiness, dizziness and visual disturbances. Drowsiness, muscle weakness and digestive disorders also occur comparatively often.
Even when used correctly, clobazam can significantly impair your ability to react. As a precaution, you should therefore not drive a motor vehicle or operate heavy machinery during the first few days of treatment.
Further information on side effects can be found in the package leaflet for your Clobazam medication. Contact your doctor or pharmacist if you develop or suspect undesirable side effects.
How to take Clobazam
Clobazam is available in the form of tablets and juice.
Clobazam tablets
Clobazam tablets are available in ten and 20 milligram strengths.
The usual starting dose for adults is 20 milligrams of clobazam per day. If necessary, this amount can be increased to 30 milligrams.
Older patients usually react more sensitively to the active substance. In this case, a daily starting dose of ten to 15 milligrams is sufficient.
The maximum daily dose for adults is 80 milligrams of clobazam.
In general, clobazam should not be taken for longer than eight to twelve weeks for the treatment of acute and chronic states of tension, agitation and anxiety.
Children from the age of six who receive clobazam as an additional treatment for their epilepsy usually start with five milligrams per day. This clozabam dose is then gradually increased to a maintenance dose of 0.3 to 1.0 milligrams per kilogram of body weight.
A special juice preparation is available for children under the age of six (see below).
Clobazam juice
Clobazam juice is available in Germany in a concentration of one or two milligrams of clobazam per milliliter. In Austria, only preparations with one milligram per milliliter are registered, in Switzerland none at all.
The dosage for children from the age of two is calculated on the basis of body weight. The usual starting dose is 0.1 milligrams of clobazam per kilogram of body weight. This is then gradually increased depending on the individual’s response to treatment.
Sometimes doctors also prescribe the juice to adolescent and adult patients (e.g. for swallowing disorders).
When should Clobazam not be taken?
Clobazam should generally not be used in the following situations:
- Hypersensitivity to the active substance or any of the other ingredients of the medicine
- myasthenia gravis (autoimmune disease of the muscles)
- Severe disorders of respiratory function
- Sleep apnea syndrome (breathing regulation disorder during sleep in which the lungs are not ventilated enough and/or not ventilated at all due to short interruptions in breathing)
- Severe liver dysfunction
- Acute intoxication with central depressants (e.g. alcohol, psychotropic drugs, sleeping pills)
- Alcohol, drug or medication addiction (current or in the past)
- breastfeeding
- in children under two years of age (due to insufficient data)
Clobazam may interact with other drugs with a sedative effect, including for example:
- Opioids (strong painkillers such as morphine and hydromorphone)
- Antipsychotics (drugs against psychotic symptoms, e.g. levomepromazine, olanzapine and quetiapine)
- Anxiolytics (anxiolytics such as gabapentin and pregabalin)
- older allergy medications (such as diphenhydramine and hydroxyzine)
In the add-on therapy of epilepsy, doctors always combine clobazam with one or more antiepileptic drugs. Interactions with these active substances are therefore of particular importance:
- Valproic acid and phenytoin, whose blood levels can rise due to clobazam
- Phenytoin, which accelerates the breakdown of clobazam
- Stiripentol and cannabidiol, which delay the breakdown of clobazam
Clobazam is broken down in the liver via the cytochrome P450 enzyme 2C19 (CYP2C19). Inhibitors of this enzyme therefore slow down the excretion of the active substance. Its dose must then usually be adjusted. Known CYP2C19 inhibitors include:
- Fluconazole (antifungal agent)
- Fluvoxamine (antidepressant)
- Omeprazole, esomeprazole (heartburn medication)
Clobazam increases the effect of muscle relaxants (muscle relaxants). This can increase the risk of falls, especially in older patients.
Inform your doctor or pharmacist about all medicines (including over-the-counter and herbal medicines) and dietary supplements that you (or your child) use. In this way, possible interactions can be clarified in advance. You will also find information on interactions in the package leaflet of the Clobazam medication.
Clobazam during pregnancy
Limited experience with the use of clobazam during pregnancy has not provided any evidence of serious malformations in the child. Nevertheless, its use in pregnancy is only recommended if the expected benefit is greater than the potential risk.
Experts at Charité – Universitätsmedizin Berlin give priority to promethazine for pregnant women with acute states of tension, agitation and anxiety. Clonazepam may be preferable for additional anti-epileptic treatment.
If you are concerned about whether you should use a clobazam medication despite being pregnant, talk to your doctor.
How to obtain medication containing clobazam
Clobazam is available on prescription in Germany, Austria and Switzerland.