Zycortal 25 mg/ml Prolonged-release Suspension for Injection for Dogs

Prior to use, gently shake the vial to resuspend the veterinary medicinal product.

Use an appropriately graduated syringe to accurately administer the required dose
volume. This is particularly important when injecting small volumes.
To ensure a correct dosage, body weight should be determined as accurately as
possible.
The use of suitably calibrated measuring equipment is recommended.
Zycortal replaces the mineralocorticoid hormones only. Dogs with combined
glucocorticoid and mineralocorticoid deficiency should also receive a glucocorticoid
such as prednisolone taking into account the current scientific knowledge.
Zycortal is intended for long term administration at intervals and doses dependent
upon individual response. Tailor the dose of Zycortal and the concurrently
administered glucocorticoid replacement therapy to the individual dog based on
clinical response and normalization of Na⁺ and K⁺
Initial dose of Zycortal:
The initial dose is 2.2 mg/kg body weight, administered by subcutaneous injection.
Interim monitoring visit:
Re-evaluate the dog and measure the serum sodium/potassium ratio (Na/K⁺ ratio)
approximately 10 days after the first dose (which is the time to maximum
concentration (Tmax) of desoxycortone). If the dog’s clinical signs have worsened or
not resolved, adjust the dose of glucocorticoid and/or investigate other causes of the
clinical signs.
Second dose of Zycortal:
At approximately 25 days after the first dose, re-evaluate the dog and measure the
Na⁺⁺

•
+
/K
+
ratio (i.e. 27 to 32)
on Day 25, adjust the dose based on the Day 10 Na⁺/K⁺ ratio using the
guidelines in Table 1, below.

•/K⁺ ratio > 32 on Day 25, either
adjust the dose based on the Day 10 Na⁺/K⁺ ratio according to Table 1 or
delay the dose (see Prolonging the dosing interval).

•⁺⁺
25, adjust the dose of glucocorticoid or Zycortal (see Subsequent doses and
long term management).
Table 1: Day 25: Administering the Second Dose of Zycortal
If the Day 10
Na⁺ ratio is:
25 days after the first dose, administer
Zycortal, as follows:
≥ 34Decrease dose to: 2.0 mg/kg body weight32 to < 34Decrease dose to: 2.1 mg/kg body weight27 to < 32Continue 2.2 mg/kg body weight≥ 24 to < 27Increase dose to: 2.3 mg/kg body weight< 24
Do not administer
Dose 2 on Day 10.
Increase dose to: 2.4 mg/kg body weight
Prolonging the dosing interval:
If the dog is clinically normal and the Day 25 Na⁺/K⁺
prolong the dosing interval instead of adjusting the dose as described in Table 1.
Evaluate the electrolytes every 5–9 days until the Na⁺/K⁺
administer 2.2 mg/kg of Zycortal.
Subsequent doses and long term management:
Once the optimal dose and dosing interval have been determined, maintain the
same regimen. If the dog develops abnormal clinical signs or Na⁺⁺ serum
concentrations, use the following guidelines for subsequent doses:
•
the polyuria/polydipsia persists and the Na⁺/K⁺ ratio is >32, then decrease the
dose of Zycortal without changing the dosing interval.
•
Increase the glucocorticoid dose.
•⁺/K⁺ ratio < 27: Decrease the Zycortal
dosing interval by 2–3 days or increase the dose.
•⁺/K⁺ ratio > 32: Decrease the Zycortal
dose.

Prior to a stressful situation, consider temporarily increasing the dose of
glucocorticoid.
In the clinical trial, the mean final dose of desoxycortone pivalate was 1.9 mg/kg
(range 1.2–2.5 mg/kg) and the mean final dosing interval was 38.7 ± 12.7 days
(range 20–99 days) with the majority of dogs having a dosing interval between 20
and 46 days.