Product description

Zycortal is a white aqueous suspension for subcutaneous use in dogs only.

Active ingredients

• Zycortal active ingredients:

  • Desoxycorticosterone pivalate 25 mg/ml

• Zycortal inactive ingredients:

  • Methylcellulose 0.5 mg
  • Sodium carboxymethylcellulose 3 mg
  • Polysorbate 60 1 mg
  • Sodium chloride 8 mg
  • Chlorocresol 1 mg
  • Water for injection

Indications for use

• Zycortal is indicated for use as replacement therapy for mineralocorticoid deficiency in dogs with primary hypoadrenocorticism (Addison’s disease).

• Before starting treatment with Zycortal, it is important that Addison’s disease has been definitively diagnosed.

Administration and dosage

• Prior to each use, thoroughly shake the vial to resuspend the product.

• Zycortal replaces the mineralocorticoid hormones only. Dogs with combined glucocorticoid and mineralocorticoid deficiency should also be treated with prednisone or prednisolone at an initial dosage of 0.2-0.4 mg/kg/day (0.1-0.2 mg/lb/day).

• Zycortal is intended for long-term administration at intervals and doses dependent upon individual response. Tailor the dose of Zycortal Suspension and the concurrently administered glucocorticoid replacement therapy to the individual dog based on clinical response and normalization of Na+ and K+ concentrations.

Initial dose of Zycortal Suspension:

• The initial dose is 2.2 mg/kg (1 mg/lb) 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 desoxycorticosterone . If the dog’s clinical signs have worsened or not resolved, adjust the dose of prednisone/prednisolone and/or investigate other causes of the clinical signs.

Second dose of Zycortal Suspension:

• At approximately 25 days after the first dose, re-evaluate the dog and repeat the Na+/K+ ratio.

• If the dog is both clinically normal and has a normal Na+/K+ ratio on Day 25, adjust the dose based on the Day 10 Na+/K+ ratio using the guidelines in the Table, below.

• If the dog is clinically normal and has a Na+/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).

• If the dog is either not clinically normal or if the Na+/K+ ratio is abnormal on Day 25, adjust the dose of prednisone/prednisolone or Zycortal Suspension (see Subsequent doses and long-term management).

Prolonging the dosing interval:

• If the dog is clinically normal and the Day 25 Na+/K+ ratio is > 32, it is possible to prolong the dosing interval instead of adjusting the dose as described in Table 1. Evaluate the electrolytes every 3-7 days until the Na+/K+ ratio is < 32, and then administer 2.2 mg/kg of Zycortal Suspension.

Subsequent doses and long-term management:

• For subsequent doses, use the following guidelines if the dog is not clinically normal and/or has abnormal Na+ or K+ concentrations:

• Clinical signs of polyuria/polydipsia: Decrease the prednisone/prednisolone dose first. If the polyuria/polydipsia persists, then decrease the dose of Zycortal Suspension without changing the dosing interval.

• Clinical signs of depression, lethargy, vomiting, diarrhea or weakness: Increase prednisone/prednisolone dose.

• Hyperkalemia, hyponatremia or Na+/K+ ratio < 27: Decrease the Zycortal Suspension dosing interval by 2-3 days.

• Hypokalemia or hypernatremia: Decrease the Zycortal Suspension dose.

• Prior to a stressful situation, consider temporarily increasing the dose of prednisone/prednisolone.

Prescribing information