The label says, word for word:
For use as replacement therapy for mineralocorticoid deficiency in dogs with primary hypoadrenocorticism (Addison's disease).
Do not use ZYCORTAL Suspension in dogs that have previously had a hypersensitivity reaction to desoxycorticosterone pivalate.
Use ZYCORTAL Suspension with caution in dogs with congestive heart disease, edema, severe renal disease or primary hepatic failure.
Desoxycorticosterone pivalate may cause polyuria, polydipsia, increased blood volume, edema and cardiac enlargement. Excessive weight gain may indicate fluid retention secondary to sodium retention.
Do not use desoxycorticosterone pivalate in pregnant dogs.
Not for human use. Keep this and all drugs out of the reach of children. Consult a physician in case of accidental human exposure.
The effectiveness of ZYCORTAL Suspension may be reduced if potassium-sparing diuretics, such as spironolactone, are administered concurrently.
Every approved medicine has a field study behind it, and the label prints what happened:
"In controlled clinical field studies, one hundred fifty-two dogs were included in the field safety analysis."
Approved by FDA under NADA # 141-444; original approval February 17, 2016 (FOI summary; sponsor Dechra, Ltd.). Label revised September 2022. The label's dosing section states: "ZYCORTAL Suspension replaces the mineralocorticoid hormones only." (dogs with combined glucocorticoid and mineralocorticoid deficiency also need glucocorticoid treatment as directed by the veterinarian).
The emergency page sorts the signs by how long you have, and the symptom checker asks what you are seeing. Reactions to a medicine can also be reported to the FDA yourself: how to report a problem.
These answers come from the approved label on DailyMed, read on 2 October 2026. Where the label does not say, the answer says so, and the vet or the pharmacist is the one to ask.
The approved use is quoted at the top of this page. It is an injection for dogs with Addison's disease that replaces a hormone they do not make enough of, the one that keeps sodium and potassium in balance.
The label gives no time for when a dog looks better. It says the drug reaches its highest level in the blood about 10 days after an injection. That is when the label has the dog checked again, with a blood test for sodium and potassium, and it has the check repeated about 25 days after the first dose.
It is an injection under the skin, and the label says to shake the vial thoroughly before each use. The label does not say who gives it, so ask the clinic. It is meant for long-term use, and the label has the vet fit both the amount and the gap between injections to the individual dog, from how the dog is doing and from the blood tests. The label says Zycortal replaces one kind of hormone only, and that dogs short of the other kind as well should also be treated with prednisone or prednisolone.
The label does not say what to do about a missed dose. Call the clinic and ask when the next injection should be.
The studies and the warnings are quoted above. The label has no line telling owners when to call the vet. Its instructions to the vet depend on signs an owner sees first: drinking and urinating more than usual, and low mood, low energy, vomiting, diarrhea or weakness. Tell the clinic if you see any of them. The label also says excessive weight gain may be a sign that the body is holding fluid. Since approval, the reactions reported most often have been pain at the injection site, low energy and vomiting, and the list also includes severe allergic reaction and collapse. The label says death or euthanasia has been associated with some of the reported events. If a person is exposed to the drug by accident, the label says to consult a physician.
The label says to store it at room temperature, 77°F, and it allows short spells between 59° and 86°F. Do not freeze it. Once the vial has been punctured for the first time, the label says to use it within 120 days. Keep it out of the reach of children.
The label says a vial is to be used within 120 days of the first puncture. For a vial that is no longer needed, the FDA's advice is as follows. The FDA says the best way to get rid of most unused or expired medicines is a take-back option: a drug take-back location, which can be at a pharmacy or a police station, or a prepaid mail-back envelope. If you cannot use one and the medicine is not on the FDA's flush list, the FDA says to mix it with something unappealing such as dirt, cat litter or used coffee grounds and to seal the mixture in a plastic bag before throwing it away. Flushing is only for medicines on that list, such as opioids. Do not give leftovers to another pet.
Write the dose, the times and the stop date here, then print this page for the fridge.
Dose and times: _____________________________________________
Stop date: _____________________________________________