Target species
Cats.
Indications for use
For the therapeutic treatment of feline primary hypertrophic cardiomyopathy.
Contraindications
Do not use in animals suffering from AV block (2nd or 3rd), hypotension or sick sinus syndrome.
Diltiazem should not be given to animals suffering from hepatic disease.
Do not use in animals suffering from renal disease.
Do not use in cats less than 12 months old.
Do not use in cats weighing less than 3 kg.
Do not use in animals that are hypersensitive to diltiazem.
Do not use in cats with severe bradycardia or arterial hypotension.
Do not use in conjunction with β blockers, digitalis or digoxin.
Do not use in pregnant or lactating females.
Special precautions for use in animals
Hepatic failure may increase the plasma concentration of diltiazem.
Monitor glucose levels carefully in diabetic animals.
Use with caution in cats suffering from congestive heart failure.
Cats with possible pre-existing thyroid problems or hyperthyroidism should be treated for this first and then reassessed, prior to commencing treatment with Diltiazem.
Clinical examination to assess the effectiveness of treatment should be performed after 8 weeks.
Cardiac rate should be monitored prior to treatment commencing and at every follow up visit.
Special precautions for the person administering the veterinary medicinal product to animals
Wash hands after use as tartrazine in the colour coating may cause allergic reaction in people who are susceptible.
In case of accidental ingestion, seek medical advice immediately and show the package insert to the physician.
Do not break tablets.
Adverse reactions
Some lethargy can occur at the beginning of treatment.
Diltiazem may cause gastrointestinal problems, e.g. constipation, vomiting and anorexia.
Rashes, skin reactions and erythema are potential side effects of diltiazem.
Bradycardia, dyspnoea, hypotension and conduction abnormalities may occasionally occur. In such cases treatment should be suspended.
Use during pregnancy and lactation
Do not use in pregnant or lactating females. Studies in laboratory animals have shown evidence of teratogenic and embryotoxic effects.
Interactions
Use with caution in conjunction with other calcium channel blockers, anticonvulsant drugs, immunosuppressant drugs, lithium, neuromuscular blocking agents and aminoglycoside antibiotics.
Concurrent use with Cimetidine or any other Histamine 2 receptor antagonists may cause an increase in plasma Diltiazem concentrations.
Gaseous anaesthetics such as halothane, isoflurane or enflurane have synergistic or additive effects with Diltiazem, which may lead to hypotension, depressed myocardial contractile function, slow junctional rhythm and AV block. Therefore, animals treated with HyperCard 10 mg and undergoing gaseous anaesthesia should be monitored closely.
Amounts to be administered and administration route
Oral.
1 tablet per cat (weighing 3.0-6.25 kg body weight) every eight hours (equivalent to 1.6-3.3 mg diltiazem hydrochloride per kg every 8 hours).
Treatment should be given for the life of the animal.
Overdose
Carry out gastric lavage and dose with activated charcoal.
For bradycardia and heart block, treat with normal saline infusion and vasopressors (Atropine, Dopamine or Isoprenaline).
Observations in humans have indicated that treatment with calcium may be useful in treating toxicity from calcium channel blocker overdose.