Comparative Pharmacology
Head-to-head clinical analysis: CALCITRIOL versus VECTICAL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CALCITRIOL versus VECTICAL.
CALCITRIOL vs VECTICAL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Calcitriol, the active form of vitamin D, binds to vitamin D receptors (VDR) in target tissues, modulating gene transcription. It increases intestinal calcium and phosphate absorption, enhances renal tubular reabsorption of calcium, and promotes bone mineralization by stimulating osteoblast activity.
VECTICAL (calcitriol) is a vitamin D analog that binds to vitamin D receptors (VDRs) in target tissues, increasing intestinal calcium absorption, renal calcium reabsorption, and enhancing osteoclast activity to mobilize calcium from bone, thereby raising serum calcium levels.
0.25-0.5 mcg orally once daily, may increase by 0.25 mcg/day at 4-8 week intervals; maximum 2 mcg/day.
1-2 mcg orally twice daily, increased every 2-4 weeks based on serum calcium and PTH levels. Maximum dose: 4 mcg twice daily.
None Documented
None Documented
Clinical Note
moderateCalcitriol + Sulfisoxazole
"The metabolism of Sulfisoxazole can be decreased when combined with Calcitriol."
Clinical Note
moderateCalcitriol + Erythromycin
"The metabolism of Erythromycin can be decreased when combined with Calcitriol."
Clinical Note
moderateCalcitriol + Cyclosporine
"The metabolism of Cyclosporine can be decreased when combined with Calcitriol."
Clinical Note
moderateCalcitriol + Fluconazole
5–8 hours (terminal) in normal renal function; prolonged up to 18–24 hours in chronic kidney disease (CKD) due to reduced clearance.
Mean terminal elimination half-life is approximately 3.7 hours (range 2.5–5.5 hours) in healthy adults. Clinically, steady-state is achieved within 2–3 days.
Renal (fecal after biliary excretion of metabolites): ~10% unchanged in urine; ~70% as metabolites in feces via bile.
Primarily hepatobiliary (74%) and fecal (14%), with renal excretion accounting for <1% of the administered dose as unchanged drug. Enterohepatic recirculation occurs.
Category A/B
Category C
Vitamin D Analog
Vitamin D Analog
"The metabolism of Fluconazole can be decreased when combined with Calcitriol."