에르고칼시페롤 (비타민 D2)

비타민 D 유사체

**에르고칼시페롤(비타민 D2)**은 지용성 비타민이자 **비타민 D 유사체**로, 수의학에서 주로 부갑상선 기능 저하증과 관련된 저칼슘혈증을 관리하는 데 사용됩니다。 * **비용 효율성**: 칼시트리올이나 디히드로타키스테롤(DHT)의 저렴한 대안으로 자주 선택됩니다. * **지연된 효과 발현**: 간 및 신장의 효소 활성화가 필요하기 때문에 활성 대사체에 비해 혈청 칼슘에 최대 효과를 나타내는 데 더 오랜 시간(5~21일)이 걸립니다. * **지속적인 독성**: 지용성이 높아 지방에 저장됩니다. 고칼슘혈증이 발생하면 약물 투여를 중단하더라도 독성 효과가 최대 18주까지 지속될 수 있습니다. > **임상 요점**: 고양이는 콜레칼시페롤(비타민 D3)에 비해 에르고칼시페롤을 25-히드록실화 형태로 효율적으로 변환하지 못합니다. 따라서 고양이 환자의 저칼슘혈증 관리에는 일반적으로 칼시트리올이 선호됩니다.

작용 기전: Ergocalciferol is an inactive prodrug that requires a two-step enzymatic activation process to regulate calcium homeostasis: 1. Ergocalciferol → **hepatic 25-hydroxylase** → 25-hydroxyvitamin D2 (calcidiol, partially active). 2. 25-hydroxyvitamin D2 → **renal 1-alpha-hydroxylase** → 1,25-dihydroxyvitamin D2 (fully active calcitriol equivalent). The active metabolite binds to intracellular **Vitamin D Receptors (VDR)**, acting as a hormone alongside parathyroid hormone (PTH) and calcitonin to: * Enhance intestinal absorption of calcium and phosphate. * Promote renal tubular reabsorption of calcium. * Increase the rate of accretion and osteoclastic resorption of minerals in bone, mobilizing calcium into the extracellular fluid.

동물 종별 용량

Cats

Maintenance therapy of parathyroid failure after using parenteral calcium to control hypocalcemic tetany · Initially 4000-6000 Units/kg PO once daily. Maintenance doses usually range from 1000-2000 Units/kg PO once daily to once weekly. · PO · once daily to once weekly · Lifelong · Patient should be hospitalized initially. Adjust dosage to maintain serum calcium concentrations between 8-9.5 mg/dL. Goal is to prevent hypocalcemic tetany, but not induce hypercalcemia.

Dogs

Maintenance therapy of parathyroid failure after using parenteral calcium to control hypocalcemic tetany · Initially 4000-6000 Units/kg PO once daily. Maintenance doses usually range from 1000-2000 Units/kg PO once daily to once weekly. · PO · once daily to once weekly · Lifelong · Patient should be hospitalized initially. Adjust dosage to maintain serum calcium concentrations between 8-9.5 mg/dL. Goal is to prevent hypocalcemic tetany, but not induce hypercalcemia.

용량은 면허 수의 전문가를 위한 임상 참고 자료입니다. 항상 최신 라벨과 개별 환자에 대해 확인하십시오.

투여 경로

금기

Hypercalcemia
Vitamin D toxicity
Malabsorption syndrome
Abnormal sensitivity to the effects of vitamin D

이상반응

Hypercalcemia
Hyperphosphatemia
Nephrocalcinosis
Soft tissue mineralization

약물 상호작용

Corticosteroids · Can reduce the effects of vitamin D analogs by decreasing calcium absorption and increasing renal excretion.
Digoxin · Patients are highly sensitive to the arrhythmogenic effects of hypercalcemia; intensified monitoring is required.
Verapamil · Patients are sensitive to the effects of hypercalcemia; intensified monitoring is required.
Mineral Oil · May reduce the amount of orally administered ergocalciferol absorbed from the GI tract.
Thiazide Diuretics · May cause hypercalcemia when given in conjunction with Vitamin D analogs due to decreased renal calcium excretion.

모니터링

Serum calcium concentrations (weekly initially, then monthly for 6 months, then every 2-3 months)
Serum phosphorus concentrations
Renal function parameters (BUN, Creatinine)
Clinical signs of hypercalcemia (PU/PD, lethargy, anorexia, vomiting)

과용량

### Acute Toxicity * The toxic acute oral dose of ergocalciferol in dogs is reported as **4 mg/kg (160,000 Units/kg)**. * **Decontamination**: Acute ingestions should be managed using established protocols for removal or prevention of GI absorption. Orally administered **mineral oil** may reduce absorption and enhance fecal elimination. ### Chronic Overdosage (Hypercalcemia) * **Immediate Action**: Temporarily discontinue ergocalciferol and any exogenous calcium therapy. * **Medical Management**: If hypercalcemia is severe, administer **0.9% normal saline** (calcium-free IV fluids), **furosemide** (to promote calciuresis), and **corticosteroids** (to decrease GI absorption and increase renal excretion of calcium). Urine acidification may also be employed. * **Prolonged Effect**: Because of the long duration of action (potentially up to 18 weeks), hypercalcemia may persist for weeks to months. Restart therapy at a reduced dosage only when calcium serum levels return to the normal range.

VetSheet 약물 레퍼런스는 면허 수의 전문가를 위한 임상 의사결정 보조 도구이며, 전문적 판단이나 제조사의 최신 라벨을 대신하지 않습니다.