POM-V
Prescription Required
Companion Animal
Epirepress 60 mg Tablets for Dogs
Active ingredient: Phenobarbital
Form
Tablet
Species
Dogs
Manufacturer
Desitin Arzneimittel GmbH
VMD MA No.
14040/4000
What it's used for
Prevention of seizures due to generalised epilepsy in dogs.
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Prescription required
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Clinical information
Epirepress 60 mg Tablets for Dogs — SPC Details
Source: VMD Summary of Product Characteristics (SPC). Last updated 26 Mar 2026.
Prevention of seizures due to generalised epilepsy in dogs.
The required dosage will differ to some extent between individuals and with the
nature and severity of the disorder.
Administration route
Only intended for oral administration in dogs.
Amount to be administered
The recommended starting dose is 2.5 mg phenobarbital per kg body weight,
administered twice daily. Any adjustments to this dose are best made on the basis of
clinical efficacy, blood concentrations and the occurrence of undesired effects.
The phenobarbital serum concentration considered to be therapeutically active is
between 20-40 μg/ml.
Steady state serum concentrations are not reached until 1-2 weeks after treatment is
initiated. The full effect of the medication occurs approximately after 2 weeks, and
doses should not be increased during this time.
The phenobarbital serum concentration may be checked after steady state has been
achieved. If it is less than 20
dosage may be increased by 20 % at a time, with associated monitoring of serum
phenobarbital levels. If seizures recur, the dose may be increased to a maximum
serum concentration of 40 μg/ml. High plasma concentrations may be associated
with hepatotoxicity.
The tablets can be divided into halves or quarters to ensure accurate dosing.
Revised: January 2025
AN: 01934/2024
Epirepress tablets can be quartered by pressing on the flat, scored upper side of the
tablet with a finger or thumb. The domed, scored lower side of the tablet should be
on a firm surface.
nature and severity of the disorder.
Administration route
Only intended for oral administration in dogs.
Amount to be administered
The recommended starting dose is 2.5 mg phenobarbital per kg body weight,
administered twice daily. Any adjustments to this dose are best made on the basis of
clinical efficacy, blood concentrations and the occurrence of undesired effects.
The phenobarbital serum concentration considered to be therapeutically active is
between 20-40 μg/ml.
Steady state serum concentrations are not reached until 1-2 weeks after treatment is
initiated. The full effect of the medication occurs approximately after 2 weeks, and
doses should not be increased during this time.
The phenobarbital serum concentration may be checked after steady state has been
achieved. If it is less than 20
dosage may be increased by 20 % at a time, with associated monitoring of serum
phenobarbital levels. If seizures recur, the dose may be increased to a maximum
serum concentration of 40 μg/ml. High plasma concentrations may be associated
with hepatotoxicity.
The tablets can be divided into halves or quarters to ensure accurate dosing.
Revised: January 2025
AN: 01934/2024
Epirepress tablets can be quartered by pressing on the flat, scored upper side of the
tablet with a finger or thumb. The domed, scored lower side of the tablet should be
on a firm surface.
Do not use in cases of hypersensitivity to the active substance(s), to any other
barbiturates or to any of the excipients.
Do not use in animals with severe impaired hepatic function.
Do not use in animals with serious renal and/or cardiovascular/respiratory disorders.
Do not use in dogs weighing less than 6 kg
Revised: January 2025
AN: 01934/2024
barbiturates or to any of the excipients.
Do not use in animals with severe impaired hepatic function.
Do not use in animals with serious renal and/or cardiovascular/respiratory disorders.
Do not use in dogs weighing less than 6 kg
Revised: January 2025
AN: 01934/2024
Ataxia, somnolence, listlessness and dizziness may occur very rarely at the start of
treatment. In some cases, these effects may persist for the entire duration of
treatment.
A paradoxical hyperexcitability may occur very rarely, particularly after first starting
therapy. As this hyperexcitability is not linked to overdosage, no reduction of dosage
is needed.
Polyuria, polydipsia and polyphagia may occur very rarely at average or higher
therapeutically active serum concentrations, but these effects are usually transient
and disappear with continued medication.
Sedation and ataxia may very rarely become significant concerns as serum levels
reach the higher end of the therapeutic range.
Hepatotoxicity may develop very rarely associated with high plasma concentrations
(> 35-40 µg/ml).
Treating dogs with phenobarbital may lower their total thyroxine levels (TT4) or free
thyroxine levels (FT4); however, this may not be an indication of hypothyroidism.
Treatment with thyroid hormone replacement should only be started if there are
clinical signs of the disease.
Revised: January 2025
AN: 01934/2024
Phenobarbital can have deleterious effects on stem cells from bone marrow.
Consequences are immunotoxic pancytopenia and/or neutropenia. These reactions
disappear after cessation of treatment.
Superficial necrolytic dermatitis may occur after administration of phenobarbital.
If adverse reactions are severe, the administered dose should be decreased.
The frequency of adverse reactions is defined using the following convention:
- very common (more than 1 in 10 animals treated displaying adverse reaction(s))
- common (more than 1 but less than 10 animals in 100 animals treated)
- uncommon (more than 1 but less than 10 animals in 1,000 animals treated)
- rare (more than 1 but less than 10 animals in 10,000 animals treated)
- very rare (less than 1 animal in 10,000 animals treated, including isolated reports)
treatment. In some cases, these effects may persist for the entire duration of
treatment.
A paradoxical hyperexcitability may occur very rarely, particularly after first starting
therapy. As this hyperexcitability is not linked to overdosage, no reduction of dosage
is needed.
Polyuria, polydipsia and polyphagia may occur very rarely at average or higher
therapeutically active serum concentrations, but these effects are usually transient
and disappear with continued medication.
Sedation and ataxia may very rarely become significant concerns as serum levels
reach the higher end of the therapeutic range.
Hepatotoxicity may develop very rarely associated with high plasma concentrations
(> 35-40 µg/ml).
Treating dogs with phenobarbital may lower their total thyroxine levels (TT4) or free
thyroxine levels (FT4); however, this may not be an indication of hypothyroidism.
Treatment with thyroid hormone replacement should only be started if there are
clinical signs of the disease.
Revised: January 2025
AN: 01934/2024
Phenobarbital can have deleterious effects on stem cells from bone marrow.
Consequences are immunotoxic pancytopenia and/or neutropenia. These reactions
disappear after cessation of treatment.
Superficial necrolytic dermatitis may occur after administration of phenobarbital.
If adverse reactions are severe, the administered dose should be decreased.
The frequency of adverse reactions is defined using the following convention:
- very common (more than 1 in 10 animals treated displaying adverse reaction(s))
- common (more than 1 but less than 10 animals in 100 animals treated)
- uncommon (more than 1 but less than 10 animals in 1,000 animals treated)
- rare (more than 1 but less than 10 animals in 10,000 animals treated)
- very rare (less than 1 animal in 10,000 animals treated, including isolated reports)
The decision to start antiepileptic drug therapy with phenobarbital should be
evaluated for each individual case and depends on number, frequency, duration and
severity of seizures in dogs.
To achieve successful therapy, administration of tablets should occur at the same
time(s) each day, and should be co-ordinated with feeding times in a consistent
manner.
Withdrawal or transition from other types of antiepileptic therapy should be made
gradually to avoid precipitating an increase in the frequency of seizures.
Some dogs are free of epileptic seizures during the treatment, but some dogs show
only a seizure reduction, and some dogs are considered to be non-responders.
Special precautions for use in animals
Caution is recommended in animals with:
- impaired hepatic and renal function
- hypovolemia, anemia and
- cardiac or respiratory dysfunction
The chance of hepatotoxic side effects can be diminished or delayed using an
effective dose that is as low as possible. Monitoring of hepatic parameters is
recommended in case of a prolonged therapy.
It is recommended to assess the clinical pathology of the patient 2-3 weeks after
start of treatment and afterwards every 4-6 months, e. g. measurement of hepatic
enzymes and serum bile acids. It is important to know that the effects of hypoxia etc.
do cause increased levels of hepatic enzymes after a seizure.
Phenobarbital may increase the activity of serum alkaline phosphatase and
transaminases. These may demonstrate non-pathological changes but could also
represent hepatotoxicity. Therefore, in the case of suspected hepatotoxicity, liver
function tests are recommended.
In stabilised epileptic patients, it is not recommended to switch between
phenobarbital formulations. However, if this cannot be avoided then additional
caution should be taken. This includes more frequent plasma concentration sampling
to ensure that therapeutic levels are maintained. Monitoring for increased side
effects and for hepatic dysfunction should be conducted more regularly until
stabilisation is confirmed.
Withdrawal of therapy with phenobarbital formulations or transition to or from another
type of antiepileptic therapy should be made gradually to avoid precipitating an
increase in the frequency of seizures.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals
People with known hypersensitivity to phenobarbital or other barbiturates should
avoid contact with this veterinary medicinal product.
Revised: January 2025
AN: 01934/2024
It is advisable to wear disposable gloves when handling the product, to reduce skin
contact.
Phenobarbital is a teratogen and developmental neurotoxicant and transfers to
breast milk.
The product should not be administered by pregnant women, women intending to
become pregnant or whose pregnancy status is unknown, as well as lactating
women.
Ingestion of Phenobarbital can cause neurotoxicity which may prove fatal. Take
utmost care that children do not come into any contact with the product. Children are
particularly at risk of intoxication. To prevent accidental ingestion of tablets, the
container should be closed immediately after withdrawing the required number of
tablets for one administration. Part tablets should be placed back into the container
and used at the next administration, as even part tablets pose a health risk to small
children if ingested. The container should be stored in a safe place out of the sight
and reach of children.
In case of accidental ingestion, seek medical advice immediately and show the
package leaflet or the label to the physician. If possible, the physician should be
informed about the time and amount of ingestion, as this information may help to
ensure that appropriate treatment is given.
Wash hands after use.
evaluated for each individual case and depends on number, frequency, duration and
severity of seizures in dogs.
To achieve successful therapy, administration of tablets should occur at the same
time(s) each day, and should be co-ordinated with feeding times in a consistent
manner.
Withdrawal or transition from other types of antiepileptic therapy should be made
gradually to avoid precipitating an increase in the frequency of seizures.
Some dogs are free of epileptic seizures during the treatment, but some dogs show
only a seizure reduction, and some dogs are considered to be non-responders.
Special precautions for use in animals
Caution is recommended in animals with:
- impaired hepatic and renal function
- hypovolemia, anemia and
- cardiac or respiratory dysfunction
The chance of hepatotoxic side effects can be diminished or delayed using an
effective dose that is as low as possible. Monitoring of hepatic parameters is
recommended in case of a prolonged therapy.
It is recommended to assess the clinical pathology of the patient 2-3 weeks after
start of treatment and afterwards every 4-6 months, e. g. measurement of hepatic
enzymes and serum bile acids. It is important to know that the effects of hypoxia etc.
do cause increased levels of hepatic enzymes after a seizure.
Phenobarbital may increase the activity of serum alkaline phosphatase and
transaminases. These may demonstrate non-pathological changes but could also
represent hepatotoxicity. Therefore, in the case of suspected hepatotoxicity, liver
function tests are recommended.
In stabilised epileptic patients, it is not recommended to switch between
phenobarbital formulations. However, if this cannot be avoided then additional
caution should be taken. This includes more frequent plasma concentration sampling
to ensure that therapeutic levels are maintained. Monitoring for increased side
effects and for hepatic dysfunction should be conducted more regularly until
stabilisation is confirmed.
Withdrawal of therapy with phenobarbital formulations or transition to or from another
type of antiepileptic therapy should be made gradually to avoid precipitating an
increase in the frequency of seizures.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals
People with known hypersensitivity to phenobarbital or other barbiturates should
avoid contact with this veterinary medicinal product.
Revised: January 2025
AN: 01934/2024
It is advisable to wear disposable gloves when handling the product, to reduce skin
contact.
Phenobarbital is a teratogen and developmental neurotoxicant and transfers to
breast milk.
The product should not be administered by pregnant women, women intending to
become pregnant or whose pregnancy status is unknown, as well as lactating
women.
Ingestion of Phenobarbital can cause neurotoxicity which may prove fatal. Take
utmost care that children do not come into any contact with the product. Children are
particularly at risk of intoxication. To prevent accidental ingestion of tablets, the
container should be closed immediately after withdrawing the required number of
tablets for one administration. Part tablets should be placed back into the container
and used at the next administration, as even part tablets pose a health risk to small
children if ingested. The container should be stored in a safe place out of the sight
and reach of children.
In case of accidental ingestion, seek medical advice immediately and show the
package leaflet or the label to the physician. If possible, the physician should be
informed about the time and amount of ingestion, as this information may help to
ensure that appropriate treatment is given.
Wash hands after use.
A therapeutic dose of phenobarbital for antiepileptic therapy can significantly induce
plasma protein (such as α1acid glycoprotein, AGP), which bind drugs. Therefore,
special attention must be paid to the pharmacokinetics and doses of drugs
simultaneously administered.
Revised: January 2025
AN: 01934/2024
The plasmatic concentration of cyclosporine, thyroid hormones and theophylline is
decreased in the case of concurrent administration of phenobarbital. The
effectiveness of these substances is diminished, too.
Concurrent use with potassium bromide increases the risk of pancreatitis.
Concurrent use with other drugs having a central depressive can result in an
increase of the effect of central depressive drugs.
Phenobarbital may enhance the metabolism of, and therefore decrease the effect of,
antiepileptics, chloramphenicol, corticosteroids, doxycycline, beta blockers and
metronidazole.
The reliability of oral contraceptives is lower.
Phenobarbital may decrease the blood concentration of griseofulvin by reducing its
absorption and/or inducing hepatic microsomal enzymes.
The following drugs can decrease the convulsive threshold: quinolones, high doses
of β-lactam antibiotic, theophyllin, aminophyllin, cyclosporine and propofol for
example). Medications which may alter the seizure threshold should only be used if
really necessary and when no safer alternative exists.
Use of phenobarbital tablets in conjunction with primidone is not recommended as
primidone is predominantly metabolized to Phenobarbital.
plasma protein (such as α1acid glycoprotein, AGP), which bind drugs. Therefore,
special attention must be paid to the pharmacokinetics and doses of drugs
simultaneously administered.
Revised: January 2025
AN: 01934/2024
The plasmatic concentration of cyclosporine, thyroid hormones and theophylline is
decreased in the case of concurrent administration of phenobarbital. The
effectiveness of these substances is diminished, too.
Concurrent use with potassium bromide increases the risk of pancreatitis.
Concurrent use with other drugs having a central depressive can result in an
increase of the effect of central depressive drugs.
Phenobarbital may enhance the metabolism of, and therefore decrease the effect of,
antiepileptics, chloramphenicol, corticosteroids, doxycycline, beta blockers and
metronidazole.
The reliability of oral contraceptives is lower.
Phenobarbital may decrease the blood concentration of griseofulvin by reducing its
absorption and/or inducing hepatic microsomal enzymes.
The following drugs can decrease the convulsive threshold: quinolones, high doses
of β-lactam antibiotic, theophyllin, aminophyllin, cyclosporine and propofol for
example). Medications which may alter the seizure threshold should only be used if
really necessary and when no safer alternative exists.
Use of phenobarbital tablets in conjunction with primidone is not recommended as
primidone is predominantly metabolized to Phenobarbital.
Store in the original container. Divided tablets should also be stored in the original
container.
Keep the container in the outer carton.
Do not store above 30°C
container.
Keep the container in the outer carton.
Do not store above 30°C
Not applicable.
5.
5.
This information is sourced from the official Summary of Product Characteristics (SPC) published by the Veterinary Medicines Directorate (VMD). It is provided for informational purposes only and does not replace professional veterinary advice. Always consult your vet before administering any medication.
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