Medication: Bromide

Your dog has been prescribed potassium bromide to control seizures. 

Key points:
• Anti-epileptic drug.
• Do not use in dogs with severe kidney disease.
• Do not use in dogs that are pregnant or lactating.
• Dosage: give with food once or twice a day.

This information sheet is designed to help answer commonly asked questions and help you give the medication safely and effectively to your pet. It does not contain all available information for this medication. If you have other questions or need more information, contact your veterinarian or pharmacist. Always follow the dosing instructions provided by your veterinarian. 

Name

• Potassium bromide (KBr). 

Brand name

• K-BroVet® (Europe & UK, US).
• Libromide® (Europe & UK, US).
• Vetbromide® (Europe).
• KBroVet-CA1 (US).

Class of drug

• Anticonvulsant. 
• Anti-epileptic drug (AED). 

Storage

• Store at room temperature in secure container. 

Your veterinarian has prescribed bromide to control seizures. Seizures are caused by abnormal electrical discharges from nerve cells in the brain. Bromide suppresses seizure activity by reducing the electrical charge within these cells. It is often used in conjunction with phenobarbital. 

Potassium bromide is given as an oral drug, given in liquid, capsule or tablet form (chewable tablets available). It should be mixed with food and is normally given once daily in the evening, or divided into two daily doses. It can also be given intra-rectally.

There are various factors that may affect the dose of bromide that your dog requires. A high salt diet means the drug will be eliminated more quickly. The converse is also true, and changing your dog's diet may increase or decrease the amount of bromide in their blood. Any changes to the diet should be made gradually (over at least 5 days) and blood concentrations of bromide should be rechecked every time your dog's diet is altered (especially if the dog becomes sedated or has unexpected seizures). Most diets have a similar salt content – with the exception of home cooked diets and prescription diets for heart disease (low salt) or for urinary stones (some are high salt). 

Blood concentrations of bromide can also increase if a dog becomes severely dehydrated, eg following severe or bloody diarrhea. If your dog appears more sedated the bromide dose may need to be temporally withdrawn or reduced. 

Ataxia and sedation may be seen at the start of therapy, after increases in doses, or with the addition of another drug (especially phenobarbitone). This effect typically wears off within a week. If it doesn’t, or is excessive, then your veterinarian may advise reducing the dose of bromide or switching your pet to another drug. If the dog is drowsy shortly after dosing then try giving the medication last thing at night. Splitting the dose, ie giving twice daily can also reduce sedation in some dogs. 

Bromide acts like a diuretic so increased urination and drinking can be seen. If your pet is receiving bromide they must always have access to water otherwise they can get dehydrated. Some animals on high doses may wet in the house overnight or when left for extended periods. 

Your pet is likely to have an increased appetite when they are on bromide therapy, however this does not mean they require more food. It may help to feed a lower calorie food so that your pet can eat more without gaining weight. 

Bromide toxicity may occur if chloride ion ingestion is reduced, eg low salt diet. Conversely, additional sodium chloride in the diet can reduce serum bromide levels, affecting seizure control. 

Epileptic dogs are at greater risk of pancreatitis, ie inflammation of the pancreas. Pancreatitis may result in clinical signs such as vomiting and anorexia and in severe cases can be life-threatening. It is likely there are multiple risk factors for this disease including obesity, persistently high resting triglyceride, a high fat diet, a tendency to scavenge and high doses of phenobarbitone combined with bromide. There are also risks for the development of an enlarged esophagus (megaesophagus) which often results in regurgitation, behavior changes and weakness in the hind legs.

In humans bromide may cause skin changes (bromism) – one of the reasons this drug is not frequently used for people. This syndrome does not appear to occur in dogs, however dogs with pre-existing skin disease, eg atopy may be itchier when receiving bromide and in some cases it may not be advisable to use this drug. 

It can take up to 4 months for the amount of bromide in your dog to be maximally effective at improving seizure control. If you want to discontinue bromide, it's best to do so gradually by slowly reducing the dosage.

Dispose of any unused bromide safely – do not flush down the toilet or sink. Ask your veterinary team if they take back medication for disposal. Do not save bromide for future use or give to other pets.

If you have given your dog a double dose, contact your veterinarian immediately – bromism can develop (see above for more information on this). 

It takes a long time for bromide to be removed from the body so it can be safe to miss a single dose (under veterinary guidance). However in normal circumstances bromide therapy should not cease suddenly otherwise your pet may have withdrawal seizures. 

If your pet is unwell, contact your veterinarian for advice.

Potassium bromide should only be given to the dog that it has been prescribed for:

• Do not give to other pets in the household.
• Do not give to dogs with severe kidney disease or those that are pregnant or lactating.
• Do not use in cats.
• If accidentally given to other pets, contact your veterinarian for advice.

If accidentally eaten by a human, speak to your primary care physician or poison control center.

Regular monitoring of bromide concentrations is essential. Your veterinarian will want to take blood samples to assess bromide concentration 8-16 weeks after your dog has started the drug. Ideally blood levels should be measured around 16 weeks after treatment starts as it takes 4 months for blood levels to stabilize after the drug is started.  

Blood concentration of bromide should also be assessed every 6-12 months, 8-16 weeks after a change in dose and if there is a breakdown in control (ie unexpected seizures).  

If seizures are still not adequately controlled (clusters of >3 seizures or seizures occurring more frequently than every 6 weeks) when the bromide serum concentration is greater than 1500 mg/l (20 mmol/l) then your veterinarian may want to consider adding or changing to another drug. 

Further information 

If you have any concerns, further information can be found on the package insert and the following websites:

Europe & UK

• Veterinary Medicines Directorate, UK (2015). Libromide.  Website: www.vmd.defra.gov.uk/productinformationdatabase/files/SPC_Documents/SPC_275636.PDF
• Veterinary Medicines Directorate, UK (2022) Vetbromide. Website: www.vmd.defra.gov.uk/productinformationdatabase/files/SPC_Documents/SPC_2041589.PDF

USA

• FDA. Freedom of Information Summary (2021) KBroVet®-CA1. Website: animaldrugsatfda.fda.gov/adafda/app/search/public/document/downloadFoi/10308

Always follow the recommended dosage and contact your veterinary team or pharmacist if you have any questions regarding your dog’s medication.