Paricalcitol (CAS 131918-61-1) is a selective vitamin D receptor agonist and a synthetic vitamin D2 analog. It primarily acts as a pharmaceutical raw material for treating secondary hyperparathyroidism in patients with chronic kidney disease (CKD), especially those on dialysis. By binding to vitamin D receptors in the parathyroid gland, it potently inhibits parathyroid hormone (PTH) synthesis and secretion, correcting mineral metabolism disorders without significantly increasing serum calcium and phosphorus levels. It is also used in pharmaceutical research to study vitamin D receptor signaling pathways and develop targeted therapies for bone metabolism disorders. Additionally, it serves as a reference standard in analytical chemistry for quality control of related drugs. With high biological activity and selectivity, it plays a vital role in nephrology and endocrinology research and drug development.

Paricalcitol is a pharmaceutical compound with potential toxicity, classified as GHS08 (Health Hazard) due to its effects on calcium metabolism. It can enter the body via oral ingestion, skin contact, or eye contact. Acute oral toxicity is moderate; overdose may cause hypercalcemia, leading to symptoms such as nausea, vomiting, constipation, polyuria, polydipsia, muscle weakness, and confusion. Severe hypercalcemia may result in renal calculi, arrhythmias, or even death. Skin contact may cause mild irritation, redness, or itching; prolonged exposure may trigger allergic reactions in sensitive individuals. Eye contact can cause irritation, tearing, and conjunctival redness. Inhalation of dust may irritate the respiratory tract, causing cough or sore throat.

Operate in a well-ventilated fume hood. Wear nitrile gloves, safety goggles, and a dust respirator. Avoid contact with strong oxidants and acids to prevent decomposition. In case of skin contact, wash thoroughly with soap and running water for 15 minutes. For eye exposure, flush with plenty of water for at least 15 minutes and seek medical attention. If ingested, do not induce vomiting; rinse mouth and seek immediate medical help. Store sealed at -20°C, away from food and incompatible substances. Transport as a non-dangerous good but keep refrigerated. Dispose of waste and containers per local regulations to avoid environmental contamination.