Potassium Bromide (/ Sodium Bromide)

What is this medication for?

• Primary or adjunctive therapy for idiopathic epilepsy, especially add-on when phenobarbital alone insufficient or liver damage develops
• 2nd/3rd-line for refractory seizures

How is it given?

Give exactly as your veterinarian prescribed — never change the dose or stop on your own unless your veterinarian has told you to.

What if I miss a dose?

• Give it as soon as you remember — unless it is almost time for the next dose (then skip the missed one; never double up).
• Call your clinic if you miss more than one dose in a row.

Side effects — what should I watch for?

Effects listed as common in this handout

• Transient drowsiness (up to 3 weeks) (Common)
• PU/PD, polyphagia/weight gain, stomach/intestinal upset (esp. with rapid loading) (Common)
• Pancreatitis (Reported, esp. combined with phenobarbital)

Worth a phone call to your veterinarian

• Toxicity: profound drowsiness→stupor, wobbliness/unsteadiness, tremors, hind-limb paresis (At levels >~15 mmol/L (some tolerate to 30))

⚠️ Contact your veterinarian or an emergency clinic IMMEDIATELY if you notice

• Lower respiratory signs (cough, trouble breathing) — can be serious/fatal (Documented, reversible on discontinuation)

Before starting (or refilling), tell your veterinarian if your pet:

• has or has had: Cats — extreme caution given pulmonary risk, some avoid entirely; renal dysfunction needs dose adjustment; keep dietary chloride constant

• is pregnant, nursing, or used for breeding
• is taking any other medications, supplements, or flea/tick products, including:
  • Diuretics (furosemide, thiazides)
  • Low/high salt diets
  • CNS sedating drugs
  • Phenobarbital

Storage and handling

Tight containers; solutions stable up to 1 year at room temperature. Refrigeration may cause precipitation (warming resolubilizes).

Good to know

• Loading dose given all at once often causes vomiting — divide over the loading period (e.g., every 6 hours ×2 days).
• Do not alter the pet's diet (especially chloride/salt content) without checking with the vet — dietary chloride changes directly shift bromide levels and seizure control.
• Bromide can falsely elevate serum chloride on some assays — be aware when interpreting electrolyte panels.