TREATMENT WITH RECTAL DIAZEPAM
CLUSTER SEIZURES IN DOGS
W.B. Thomas DVM, MS, Dipl. ACVIM (Neurology)
The purpose of this
article is to provide general information about home treatment with rectal diazepam
(valium) for dogs with cluster seizures. It discusses the treatment recommended by
the Neurology/Neurosurgery service at the Veterinary Teaching Hospital, College of
Veterinary Medicine, University of Tennessee. Because clinical circumstances vary
widely and each patient is unique, specific recommendations can only be made by the
Why is home treatment
necessary for some dogs?
Most dogs with idiopathic epilepsy suffer isolated seizures that stop spontaneously
within one to three minutes. However, some dogs with epilepsy tend to suffer cluster
seizures or status epilepticus. Status epilepticus is
defined as (1) a continuous seizure lasting at least 5 minutes or (2) two or more discrete
seizures without full recovery of consciousness between seizures. Cluster
seizures (serial seizures, acute repetitive seizures) are two or more seizures
occurring over a brief period (minutes to hours) but with the patient regaining
consciousness between the seizures.1
While a single seizure of short duration is rarely life-threatening, status epilepticus
is a medical emergency requiring prompt treatment. Continuous seizure activity
lasting 30 to 60 minutes can lead to profound, life-threatening abnormalities and brain
damage. 2 Although cluster seizures do not fulfill the
definition of continuous seizure activity, they nevertheless represent a serious condition
that can progress to status epilepticus. The goal of treatment is to quickly stop
the seizure and provide support for the patient. Typically, this involves urgent
veterinary care, including administering anti-seizure medication by vein. The
financial and emotional distress of repeated emergency treatment is a common reason for a
client to have an epileptic pet euthanized.
Why is rectal
administration of diazepam recommended?
Rectal administration of diazepam (valium) by the client is a safe method of home
treatment of cluster seizures in dogs with idiopathic epilepsy.3
Diazepam belongs to the class of drugs known as benzodiazepines. Benzodiazepines are
the treatment of choice for the emergency treatment of seizures because they are safe,
work quickly, and are effective against many types of seizures. Veterinarians
typically administer diazepam by vein to quickly stop a seizure, but most clients are not
adept at intravenous injections. Absorption of diazepam after injection into the muscle is
variable and unpredictable and may cause muscle damage.4
Giving diazepam by mouth is difficult and hazardous when the dog is actively seizing, and
absorption after oral administration is slow and unpredictable.4 On the other
hand, rectal administration of diazepam results in higher and earlier blood levels
compared with either oral or intramuscular routes, making this route of administration
ideal for home treatment of cluster seizures.4
Which dogs are candidates
for home treatment with rectal diazepam?
This treatment is considered in dogs with a tendency to suffer multiple seizures during
a 24-hour period. A primary goal of treatment in these dogs is to prevent the
seizures with daily anti-seizure medication. If this is not totally successful and
the patient still tends to suffer cluster seizures, then home treatment with rectal
diazepam should be considered. This treatment is not recommended for the majority of dogs
with idiopathic epilepsy that tend to suffer single, isolated seizures.
How is the treatment
This treatment uses commercially available diazepam injectable solution. Although
this solution is intended for injection by vein, studies have shown that this product is
absorbed well when given rectally. The syringe is filled with the appropriate dose
of diazepam and then attached to a 1-inch teat cannula or similar device. This is
inserted approximately one inch (2 cm) into the dog's rectum and the syringe's plunger is
pushed, delivering the diazepam. The first treatment is given as soon as possible
after the onset of a seizure. The same dose can be repeated for a total of 3 times within
a 24-hour period. If the seizures do not stop or if the dog appears to be having
difficulty breathing, the pet should be taken to a veterinarian for emergency treatment.
What dose of diazepam is
Each patient is different, so specific recommendations can only be made by the attending
veterinarian. A dose of 2 mg per kg of body weight is usually recommended for dogs
taking Phenobarbital (Phenobarbital is known to increase the dose requirement for
diazepam).5 In dogs not taking Phenobarbital, the dose
is usually 0.5 to 1 mg per kg.
Isn't this a high dose of
The rectal dose is higher than the intravenous dose in order to obtain adequate blood
levels. Also, as mentioned above, long-term treatment of Phenobarbital increases the
dose requirement as well. These doses have been found to be quite safe in
experimental studies in dogs.5
What about diazepam
Some pharmacists can compound diazepam suppositories. Also, a gel formulation of diazepam
(Diastat) has recently become available for rectal administration in human patients.6 However, these are not currently recommended because the
absorption of these products has not been studied in dogs.
Is it legal for me to have
In the United States, diazepam is a prescription drug. Clients need to obtain the
diazepam from their veterinarian or have a prescription from their veterinarian in order
to obtain diazepam from a pharmacy. Diazepam is also a controlled substance, as is
Phenobarbital. This means there are certain additional requirements the veterinarian must
follow when writing a prescription for or dispensing the drug. The purpose of
controlled substance regulations is to minimize inappropriate use of these drugs, not
prevent their beneficial use in patients that need such therapy. Because injectable
diazepam solution is used mostly in hospitals, many pharmacies do not carry this
product. However, it can usually be obtained from hospital pharmacies or ordered by
a pharmacist or veterinarian.
Address questions or
W.B. Thomas DVM, MS, Dipl. ACVIM (Neurology)
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Lothman EL. The biochemical basis and pathophysiology of status epilepticus. Neurology
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Podell M. The use of diazepam per rectum at home for the acute management of cluster
seizures in dogs. J.Vet.Int.Med. 1995; 9:68-74.
Papich MG, Alcorn J. Absorption of diazepam after its rectal administration in dogs.
Am.J.Vet.Res 1995; 56:1629-1636.
Wagner SO, Sams RA, Podell M. Chronic phenobarbital therapy reduces plasma benzodiazepine
concentrations after intravenous and rectal administration of diazepam in the dog.
J.Vet.Pharmacol.Therap. 1998; 21:335-341.
Dreifuss FE, Rosman NP, Cloyd JC, Pellock JM, Kuzniecky RI, Lo WD, et al. A comparison of
rectal diazepam gel and placebo for acute repetitive seizures. New Engl.J.Med. 1998;