Calcitriol Solution
Calcitriol is a compounded formulation containing Calcitriol, prepared by Mixlab for veterinary use. Available by prescription.
The uses and pharmacology described below reflect the FDA-approved labeling for this active ingredient; your veterinarian determines whether and how they apply to your animal's treatment plan.
Veterinarians most commonly consider calcitriol for patients presented with hypocalcemia (low blood calcium) resulting from chronic renal insufficiency or hypoparathyroidism. In the context of cardiorenal health, calcitriol may be discussed as part of a management approach for secondary hyperparathyroidism, a condition often observed as kidney function declines and the body struggles to regulate parathyroid hormone (PTH) levels. By supplying the active form of vitamin D directly, your veterinarian can manage the physiological signals that control mineral absorption when the kidneys are no longer able to perform the final activation step of vitamin D.
At a pharmacological level, calcitriol acts as a high-affinity ligand for the vitamin D receptor (VDR) found in the intestines, bones and kidneys. Once bound to these receptors, the medication stimulates the synthesis of calcium-binding proteins, which increases the active transport of calcium and phosphorus across the intestinal mucosa and into the bloodstream. It also interacts with the parathyroid glands to provide negative feedback, stopping the excessive secretion of PTH. Because calcitriol does not require activation by the kidneys or liver, it provides a mechanism for immediate biological activity in patients with organ compromise. Your veterinarian will determine the clinical appropriateness of calcitriol based on ionized calcium levels, phosphorus concentrations and overall metabolic diagnostic testing.
Prescription only. Use only under the direction of a licensed veterinarian. This information is not a substitute for veterinary diagnosis, prescribing or monitoring. Compounded drugs are not approved by the FDA for safety or effectiveness.
Commonly observed effects associated with calcitriol administration include localized digestive changes such as vomiting or a decrease in appetite. The most significant clinical priority when utilizing this prescription is the risk of hypercalcemia (excessive blood calcium), which can manifest as increased thirst, increased urination or significant lethargy. Because the margin between therapeutic and toxic levels is narrow, your veterinarian will direct frequent blood work to monitor calcium and phosphorus levels closely. Owners should watch for signs of persistent weakness or unusual behavior and contact their veterinarian promptly with any concerns.
This medication is typically used with extra caution or avoided in patients with pre-existing hypercalcemia, vitamin D toxicity or high serum phosphorus levels, as calcitriol increases the absorption of both minerals. If phosphorus levels are not managed before starting calcitriol, there is a risk of soft tissue mineralization. Before starting a protocol, ensure your veterinarian has a complete history of all other supplements and medications your pet is receiving, especially those containing calcium or other vitamin D analogs. Your veterinarian is the right person to provide guidance on the necessary monitoring frequency and the proper administration method to ensure the management approach remains suitable for your pet's individual health status.
Yes. Calcitriol is a highly potent prescription medication and can only be dispensed by a licensed pharmacy upon receipt of a valid authorization from a licensed veterinarian. Mixlab verifies all authorizations before any medication is prepared or shipped to your home.
Yes. Because calcitriol is required in extremely precise, microgram-level doses that are often much smaller than available human commercial products, Mixlab specializes in compounding it into customized strengths. Your veterinarian may prescribe it in a flavored oral liquid or small capsule to suit your pet’s specific weight and needs.
Veterinarians discuss calcitriol specifically because it is the "active" form of the vitamin that the body usually makes on its own. In pets with certain conditions, like kidney disease, the body can no longer convert standard vitamin D into this active form, so calcitriol is used to provide the specific signal the body needs to absorb calcium.
If your pet is taking calcitriol, you should monitor for observational signs of high calcium such as a sudden increase in drinking and urinating, a noticeable loss of appetite or vomiting. If you observe any of these changes, contact your veterinarian immediately, as they will need to perform blood work to check your pet’s mineral levels.
