Ketoconazole is an antifungal used in cats to eliminate skin, systemic and bone mycoses, acting against fungi as varied as the dermatophytes responsible for ringworm, yeasts such as candida or malassezia and systemic fungi such as aspergillus or histoplasma. This drug has a fungistatic and sporicidal effect because it destroys the balance of the cell membrane of the fungus by binding to an enzyme that synthesizes the compound that balances and favors the proper functioning of the cell membranes of the fungus, essential for its survival and proliferation..
What is Ketoconazole?
Ketoconazole is a broad-spectrum active ingredient from the group of antifungals, that is, the drugs intended to treat fungi In concrete is a fungistatic of the azole group, a synthetic derivative of imidazole and the first oral antifungal with a broad spectrum.
Ketoconazole's mechanism of action does not differ from that of other imidazole antifungals, so damages fungal cell membranes Specifically, This active ingredient is responsible, through binding with the P-450 enzymes of the fungus cytochrome with great affinity, to inhibit the synthesis of ergosterol, which is a compound present in the cell membranes of the fungus and that fulfills a function similar to cholesterol of mammalian cells, that is, it is capable of modifying the permeability and fluidity of the membrane and of regulating some cellular proteins. Due to this, the cell membrane of the fungus does not fulfill its functions, becoming defective.
The absorption of Ketoconazole in cats is very rapid orallybeing highly lipophilic, especially if administered with food. Ketoconazole binds to albumin and other plasma proteins and exhibits a large volume of distribution, reaching high concentrations in the :
- Kidneys
- Lungs
- Liver
- Pancreas
- Adrenal glands
- Skin
Ketoconazole is metabolized in the liver and eliminated primarily in the bile and, to a lesser extent, in the urine by the kidneys.
What is Ketoconazole used for in cats?
Ketoconazole in cats is used as a broad-spectrum fungistatic and sporocidal antimycotic, due to its effective systemic action for the treatment of fungi from different locations and genres. Specifically, Ketoconazole's antifungal spectrum can be effective against the following fungi and yeasts:
- Aspergillus
- Blastomyces
- Cryptococcus
- Histoplasma
- Candida
- Microsporum
- Trichophyton spp.
- Malassezia
- Dermatiaceous Fungi
- Pythium
- Pseudomycetomas
In addition, Ketoconazole also has antiglucocorticoid and antiandrogenic effects, inhibiting the conversion of cholesterol to steroid hormones such as cortisol and testosterone, also through the inhibition of cytochrome P450 enzymes that are also involved in its synthesis.
Ketoconazole dosage for cats
When we talk about Ketoconazole for cats, we have to take into account that we can do it from the point of view of the medicine through the topical route or, if not, through the oral route. Therefore, the dose of ketoconazole for cats will depend on:
- The medicine presentation form.
- Your concentration on the product.
Topical Ketoconazole Dosage for Cats
Ketoconazole in cats can be used topically for mild or moderate mycosis located at the skin level. Generally in the same cream we can also find other components such as omega 6 fatty acids for their pro-inflammatory action, making the cat's immune system go to the area and act against the fungi involved and zinc oxide to regenerate the epidermis. It is usually used twice a day, applying the exact amount defined by the patient information leaflet and the veterinarianand the application should be stopped one week after the remission of the lesions. There are also complementary treatments such as ketoconazole shampoos.
Ketoconazole Oral Dosage for Cats
Another way of using Ketoconazole is orally, administered together with food and in tablet form. The dose of Ketoconazole in cats ranges from 5 to 10 mg/kg every 24 hours In cutaneous mycoses, treatment usually lasts about three weeks, while in cases of mycosis at the bone level the treatment is longer, requiring a duration of 2 or 3 months and in all cases the treatment must be extended for another week after remission of the clinical signs of the disease.
Ketoconazole Side Effects for Cats
In cats, the side effects of ketoconazole are mainly at the digestive level, although the spectrum of undesirable effects after the use of this active principle in cats are the following:
- Anorexia or decreased appetite
- Vomiting
- Diarrhea
- Abdominal pain
- Lethargy
- Jaundice
- Platelets decreased
- Neurological signs such as: tremors, ataxia and apathy
The incidence of these side effects is higher if there is a Ketoconazole overdose in the cat For this reason never give Ketoconazole to your cat without first going through a veterinary prescription where your veterinarian will apply the specific dose for your little feline according to its individual characteristics.
Contraindications of Ketoconazole for cats
The use of ketoconazole in cats is contraindicated in all of the following cases:
- Cats with known hypersensitivity to the drug or any of its excipients.
- Cats with liver failure.
- Cats with thrombocytopenia: low platelet count.
- Kittens less than 1 month.
- Gatas pregnant.
- Cats with kidney disease and stressed cats: the drug must be used with care.
It is important to note that Ketoconazole cannot be usedwhen you are taking antacids or H2 receptor antagonist drugs such as ranitidine or cimetidine, as well as proton pump inhibitors such as omeprazole since these make the stomach pH more alkaline and ketoconazole requires an acid medium for absorption.
Other drugs that should not be used together with ketoconazole because they reduce the elimination of other drugs metabolized by cytochrome P450 are the following:
- Cyclosporins.
- Cisapride.
- Midazolam.
- Macrolides: clarithromycin, erythromycin.
- Amlodipine.
- Fentanyl.
- Phenobarbital.
- Digoxin.
- Anticoagulants.
- Macrocyclic lactones: ivermectin, selamectin, milbemycin.
- Amitriptyline.
- Theophylline.
- Vincristine.
- Vinblastine.
