Vitamin D (Dosing, Interaction, Side Effect, Administration, Etc..)

DRUG CLASS:
Nutriceutical
Nutritive Agent

Vitamin D

DOSING:
Adult Dose:
Falls; Prophylaxis:
51 to 70 years:
600 international units/day is recommended for at-risk patients

Older than 70 years:
800 international units/day is recommended for at-risk patients

Familial x-linked hypophosphatemic vitamin D refractory rickets:
12000 to 500000 international units ORALLY daily

Hypoparathyroidism:
50000 to 200000 international units ORALLY once daily (plus calcium lactate 4 g 6 times daily)

Vitamin D deficiency

(NON-FDA LABELED INDICATION):
50000 international units ORALLY every week for 8 to 12 weeks; may repeat another 8 to 12 weeks if 25-hydroxyvitamin D levels are less than 30 nanograms/milliliter (ng/mL)

(Malabsorption syndrome)
50000 international units ORALLY every day or every other day

(Granulomatous disorders and some lymphomas)
50000 international units ORALLY once a week for 4 weeks or every 2 to 4 weeks; maintain 25-hydroxyvitamin D levels between 20 and 30 ng/mL
(Nephrotic syndrome) 50000 international units ORALLY twice a week for 8 to 12 weeks; may repeat another 8 to 12 weeks if 25-hydroxyvitamin D levels are less than 30 ng/mL

(Chronic kidney disease stage 3 or 4; 25-hydroxyvitamin D levels less than 5 ng/mL)
50000 international units ORALLY every week for 12 weeks; then monthly for 6 months

(Chronic kidney disease stage 3 or 4; 25-hydroxyvitamin D levels between 5 and 15 ng/mL)
50000 international units ORALLY weekly for 4 weeks; then monthly for 6 months

(Chronic kidney disease stage 3 or 4; 25-hydroxyvitamin D levels between 16 and 30 ng/mL)
50000 international units ORALLY monthly for 6 months

(Chronic kidney disease stage 5)
50000 international units ORALLY weekly for 24 weeks

Vitamin D deficiency

; Prophylaxis:
200 international units/day; ages 50 to 70; 400 international units/day; over age 70; 600 international units/day

Pediatric Dose:
Familial x-linked hypophosphatemic vitamin D refractory rickets:
12000 to 500000 international units ORALLY daily;

dosage

must be individualized
(neonatal) initial; 2000 to 4000 international units ORALLY once daily for 6 to 12 weeks; then 200 to 400 international units/day

Hypoparathyroidism:
50000 to 200;000 international units ORALLY once daily (plus calcium lactate 4 g 6 times daily);

dosage

must be individualized

Vitamin D deficiency

; Prophylaxis:
Total daily intake requirement of at least 400 international units/day beginning first few days of life to maintain serum 25-hydroxyvitamin D serum concentrations at 50 nmol/L or greater (20 nanograms/milliliter or greater)

MECHANISM OF ACTION:
Ergocalciferol; or vitamin D(2); promotes active absorption of calcium and phosphorus; thus increasing serum calcium and phosphate levels sufficiently to allow bone mineralization. It also mobilizes calcium and phosphate from bone and increases the reabsorption of calcium and phosphate by the renal tubules.

ADVERSE EFFECT:
Common:
Gastrointestinal:
Constipation
Loss of appetite
Nausea

Serious:
Endocrine metabolic:
Hypercalcemia
Hypervitaminosis D

CONTRAINDICATION:
Abnormal sensitivity to the toxic

effects of vitamin D

Hypercalcemia
Hypervitaminosis D
Malabsorption syndrome

DRUG INTERACTION:
Contraindicated:
Burosumab-twza(Theoritical)

PHARMACOKINETICS:
Metabolism:
Hepatic and Renal; hydroxylation
Metabolites: 25-hydroxyvitamin D and 1;25-dihydroxyvitamin D

Excretion:
Dialyzable:Yes

PRECAUTION:
Adequate dietary calcium; necessary for clinical response to

vitamin D therapy

Evaluate

vitamin D intake

from fortified foods;

dietary supplements

; and self-administered and prescription drug sources
Hyperphosphatemia may occur; must maintain normal serum phosphorus levels by aluminum gel administration and/or dietary phosphate restriction to prevent metastatic calcification

Hypersensitivity to vitamin D

; particularly in infants with idiopathic hypercalcemia
hypoparathyroidism; dihydrotachysterol; intravenous calcium; and/or parathyroid hormone may be required during treatment
Tartrazine (FD&C Yellow No. 5) sensitivity; increased risk of allergic reactions including bronchial asthma in susceptible patients; especially in patients with concomitant aspirin sensitivity
Vitamin D-resistant rickets; the range between therapeutic and toxic doses is narrow

PREGNENCY CATEGORY:
C (FDA)

BREAST FEEDING:
AAP: Maternal medication usually compatible with breastfeeding
WHO: Compatible with breastfeeding

MONITORING:
Serum calcium, serum phosphorus; every 2 wk or more frequently
Bone X-ray; monthly

DOSAGE FORM:
Oral Capsule:
2000 IU
50000 IU

Oral Capsule; Liquid Filled:
50000 IU

Oral Solution:
8000 IU/1 ML
400 IU/0.05 ML

Oral Tablet:
400 IU
2000 IU

TREATMENTS:
MILD TO MODERATE TOXICITY:
Monitor serum calcium and phosphorus concentrations. Discontinue

all vitamin D

and

calcium supplements

; start a low-calcium diet. Increase oral fluids or IV fluids, if patient is unable to tolerate fluids, to increase renal calcium clearance. Diuresis with IV 0.9% NaCl and furosemide can be used to promote calcium excretion.

SEVERE TOXICITY: HYPERCALCEMIA:
Monitor serum calcium and phosphorus concentrations until levels have stabilized, discontinue

all supplements

. Administer IV 0.9% saline and furosemide to enhance calcium elimination. Corticosteroids: Hydrocortisone: 100 mg/day OR Prednisone: 20 mg/day can improve hypercalcemia and hypercalcuria. Bisphosphonates (eg, pamidronate 90 mg IV; alendronate) have been used successfully to treat severe hypercalcemia. Calcitonin has also been used. Hemodialysis may be indicated in patients with severe hypercalcemia that is unresponsive to other treatment. Cardiac dysrhythmias may develop, obtain a baseline ECG and continuous cardiac monitoring.

SEIZURES:
Treat initially with benzodiazepines, followed by barbiturates as needed.

OTHER:
Monitor CNS and renal function.

TOXICOLOGY:
TOXICITY: A specific toxic dose has not been established. Toxicity has been reported after Vitamin D intake of 50,000 to 150,000 International Units daily for prolonged periods. Two adults ingested

supplements

containing large doses (manufacturing error) of vitamin D (1,864,000 and 970,000 International Units

vitamin D3 daily

, respectively) daily for several months and developed significant toxicity and prolonged elevated concentrations of 5-hydroxyvitamin D for up to a year. However, no permanent sequelae developed. A 3-month-old inadvertently received 12000 International Units of vitamin D daily for approximately 20 days; a serum 25-hydroxyvitamin D level was elevated (422 ng/mL), but no symptoms developed. In a similar case, a 2-month-old received 12000 International Units of vitamin D for approximately 30 days; a serum 25-hydroxyvitamin D level was markedly increased (750 ng/mL) along with hypercalcemia. The infant recovered completely following supportive care. Two elderly patients developed no evidence of clinical effects after inadvertently receiving 2,000,000

International Units of Vitamin D3

.

PATIENT COUNSELING OR CLINICAL TEACHING:
Warn patient to report symptoms of hypercalcemia.
Side effects with excessive use may include nausea; anorexia; weight loss; constipation; polyuria; polydipsia; hypertension; weakness; and muscle aches or stiffness.
Instruct patient to maintain adequate intake of calcium with drug.
Advise patient to avoid additional

vitamin D supplements

.




Disclaimer:
For the Registered Medical Practitioner Only. We are not recommended for self medication. self medication is may harmful for health. We are only Provide information about medicine.