Vitamin D3 400iu Tablets
It is used to treat or prevent vitamin D deficiency.
Drug Class
Vitamin, Nutritional Supplement
Pharmacologic Class
Vitamin D analog
Pregnancy Category
Category A (when taken in recommended daily allowances); Category C (when taken in doses above recommended daily allowances)
FDA Approved
Jan 1970
DEA Schedule
Not Controlled
Overview
What is this medicine?
Vitamin D3 is a vitamin that helps your body absorb calcium and phosphorus, which are important for strong bones and teeth. It also plays a role in muscle function and immune health. This 400 IU tablet is a common daily dose to help maintain healthy vitamin D levels.
How to Use This Medicine
Taking Your Medication Correctly
To ensure you get the most benefit from your medication, it's essential to follow your doctor's instructions carefully. Read all the information provided with your medication and follow the instructions closely. Some medications should be taken with food, while others should be taken on an empty stomach. If you're unsure, consult with your pharmacist to determine the best way to take your medication.
It's also important to note that some strengths of this medication may not be taken every day. Make sure you understand your medication schedule and talk to your doctor if you have any questions or concerns.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication, store it at room temperature, protected from light, and in a dry place. Avoid storing your medication in a bathroom, as the moisture and humidity can affect its potency. Keep all medications in a safe and secure location, out of the reach of children and pets.
When disposing of unused or expired medications, do not flush them down the toilet or pour them down the drain unless instructed to do so by your pharmacist. Instead, throw them away in a responsible manner. You can also check with your pharmacist to see if there are any drug take-back programs in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular medication schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
To ensure you get the most benefit from your medication, it's essential to follow your doctor's instructions carefully. Read all the information provided with your medication and follow the instructions closely. Some medications should be taken with food, while others should be taken on an empty stomach. If you're unsure, consult with your pharmacist to determine the best way to take your medication.
It's also important to note that some strengths of this medication may not be taken every day. Make sure you understand your medication schedule and talk to your doctor if you have any questions or concerns.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication, store it at room temperature, protected from light, and in a dry place. Avoid storing your medication in a bathroom, as the moisture and humidity can affect its potency. Keep all medications in a safe and secure location, out of the reach of children and pets.
When disposing of unused or expired medications, do not flush them down the toilet or pour them down the drain unless instructed to do so by your pharmacist. Instead, throw them away in a responsible manner. You can also check with your pharmacist to see if there are any drug take-back programs in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular medication schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
Lifestyle & Tips
- Take with food, especially a meal containing fat, to improve absorption.
- Sun exposure (10-30 minutes of midday sun several times a week) can help your body produce Vitamin D, but be mindful of skin cancer risk.
- Include Vitamin D-rich foods in your diet (e.g., fatty fish like salmon, mackerel, fortified milk, cereals, and orange juice).
Available Forms & Alternatives
Available Strengths:
- Vitamin D3 50,000 IU (chole) Cap
- Vitamin D3 2,000unit Capsules
- Vitamin D3 5,000 IU (chole) Tab
- Vitamin D3 2,000iu Tablets
- Vitamin D3 1,000 Unit Tablets
- Vitamin D3 400unit Chw Tablets
- Vitamin D3 1,000unit Chew Tablets
- Vitamin D3 10,000unt Capsules
- Vitamin D3 5000 Unit Capsules
- Vitamin D3 50mcg Tablets
- Vitamin D3 400iu Tablets
- Vitamin D3 1.25mg Capsules
- Vitamin D3 5,000iu Drops
- Vitamin D3 5000 Unit Capsules
Dosing & Administration
Adult Dosing
Standard Dose:
400 IU (10 mcg) orally once daily for general health/maintenance
Dose Range:
400 - 1000 mg
Condition-Specific Dosing:
deficiency_prevention:
600-800 IU daily
deficiency_treatment:
Often much higher doses (e.g., 50,000 IU weekly or 2,000-4,000 IU daily) under medical supervision
Pediatric Dosing
Neonatal:
400 IU (10 mcg) orally once daily (AAP recommendation for breastfed infants)
Infant:
400 IU (10 mcg) orally once daily
Child:
400-600 IU (10-15 mcg) orally once daily
Adolescent:
600 IU (15 mcg) orally once daily
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment needed for 400 IU dose.
Moderate:
No specific adjustment needed for 400 IU dose. Monitor calcium and phosphate. Higher doses for deficiency may require calcitriol.
Severe:
No specific adjustment needed for 400 IU dose. Monitor calcium and phosphate. Higher doses for deficiency may require calcitriol, as cholecalciferol requires renal activation.
Dialysis:
No specific adjustment needed for 400 IU dose. Monitor calcium and phosphate. Higher doses for deficiency may require calcitriol, as cholecalciferol requires renal activation.
Hepatic Impairment:
Mild:
No specific adjustment needed.
Moderate:
No specific adjustment needed.
Severe:
No specific adjustment needed. Impaired 25-hydroxylation may occur, but generally not an issue for maintenance doses.
Pharmacology
Mechanism of Action
Cholecalciferol (Vitamin D3) is a fat-soluble vitamin that is metabolically inert. It is hydroxylated in the liver to 25-hydroxyvitamin D (calcifediol or calcidiol) and then in the kidneys to 1,25-dihydroxyvitamin D (calcitriol), the active hormonal form of Vitamin D. Calcitriol acts on target tissues (intestine, bone, kidney, parathyroid glands) to regulate calcium and phosphate homeostasis, promote intestinal absorption of calcium and phosphate, and regulate bone mineralization.
Pharmacokinetics
Absorption:
Bioavailability:
Highly variable, depends on fat intake and individual factors. Approximately 50-80% from dietary sources.
Tmax:
Approximately 10-12 hours for 25(OH)D after a single dose.
FoodEffect:
Enhanced absorption when taken with fatty meals.
Distribution:
Vd:
Large, distributed into adipose tissue and muscle.
ProteinBinding:
Primarily bound to vitamin D-binding protein (DBP) and albumin.
CnssPenetration:
Limited
Elimination:
HalfLife:
Terminal half-life of 25(OH)D is approximately 15-30 days. Half-life of 1,25(OH)2D is approximately 4-6 hours.
Clearance:
Not readily quantifiable as a single value due to storage and slow turnover.
ExcretionRoute:
Primarily biliary/fecal, with some renal excretion of metabolites.
Unchanged:
Minimal
Pharmacodynamics
OnsetOfAction:
Effects on calcium and phosphate levels are gradual, typically over days to weeks.
PeakEffect:
Peak increase in 25(OH)D levels occurs weeks after initiation of daily dosing.
DurationOfAction:
Due to storage in adipose tissue and long half-life of 25(OH)D, effects can persist for weeks to months after discontinuation of high doses.
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing
+ Tightness in the chest or throat
+ Difficulty breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of high calcium levels, including:
+ Weakness
+ Confusion
+ Fatigue
+ Headache
+ Nausea and vomiting
+ Constipation
+ Bone pain
Other Possible Side Effects
Like all medications, this drug can cause side effects. However, many people do not experience any side effects or only have mild ones. If you have any side effects that bother you or do not go away, contact your doctor for advice.
Reporting Side Effects
Not all possible side effects are listed here. If you have questions or concerns about side effects, discuss them with your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin (with or without fever)
+ Wheezing
+ Tightness in the chest or throat
+ Difficulty breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Signs of high calcium levels, including:
+ Weakness
+ Confusion
+ Fatigue
+ Headache
+ Nausea and vomiting
+ Constipation
+ Bone pain
Other Possible Side Effects
Like all medications, this drug can cause side effects. However, many people do not experience any side effects or only have mild ones. If you have any side effects that bother you or do not go away, contact your doctor for advice.
Reporting Side Effects
Not all possible side effects are listed here. If you have questions or concerns about side effects, discuss them with your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Signs of too much vitamin D (hypercalcemia): nausea, vomiting, constipation, loss of appetite, increased thirst, increased urination, muscle weakness, fatigue, confusion, kidney stones.
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction and its symptoms.
Certain health conditions, including:
+ Malabsorption syndrome
+ Overactive parathyroid gland
+ Sarcoidosis
+ Elevated levels of vitamin D or calcium in your body
+ Williams syndrome
This list is not exhaustive, and it is crucial to discuss all your health problems and medications with your doctor.
To ensure your safety, please provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter medications you are taking
Natural products and vitamins you are using
* Any health problems you have
It is vital to verify that it is safe to take this medication with all your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction and its symptoms.
Certain health conditions, including:
+ Malabsorption syndrome
+ Overactive parathyroid gland
+ Sarcoidosis
+ Elevated levels of vitamin D or calcium in your body
+ Williams syndrome
This list is not exhaustive, and it is crucial to discuss all your health problems and medications with your doctor.
To ensure your safety, please provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter medications you are taking
Natural products and vitamins you are using
* Any health problems you have
It is vital to verify that it is safe to take this medication with all your other medications and health conditions. Never start, stop, or change the dose of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. To avoid excessive intake, do not take any additional supplements or medications containing vitamin D without consulting your doctor. If you are pregnant, planning to become pregnant, or are breastfeeding, notify your doctor immediately. Your doctor will discuss the potential benefits and risks of this medication with you, considering both your health and the health of your baby, to determine the best course of action.
Overdose Information
Overdose Symptoms:
- Severe hypercalcemia symptoms (as listed above), leading to kidney damage, heart rhythm problems, and coma in extreme cases.
What to Do:
Discontinue vitamin D and calcium supplements. Seek immediate medical attention. Call 1-800-222-1222 (Poison Control).
Drug Interactions
Major Interactions
- Thiazide diuretics (increased risk of hypercalcemia)
- Digoxin (increased risk of arrhythmias due to hypercalcemia)
Moderate Interactions
- Corticosteroids (may reduce vitamin D effects)
- Anticonvulsants (e.g., phenytoin, carbamazepine, phenobarbital - may increase vitamin D metabolism, leading to deficiency)
- Bile acid sequestrants (e.g., cholestyramine, colestipol - may impair vitamin D absorption)
- Mineral oil (may impair vitamin D absorption)
- Orlistat (may impair vitamin D absorption)
Monitoring
Baseline Monitoring
Serum 25-hydroxyvitamin D [25(OH)D]
Rationale: To assess baseline vitamin D status, especially if deficiency is suspected or higher doses are considered. Not typically needed for routine 400 IU supplementation in healthy individuals.
Timing: Prior to initiation of supplementation (if indicated)
Serum Calcium
Rationale: To assess baseline calcium levels and identify pre-existing hypercalcemia. Not typically needed for routine 400 IU supplementation.
Timing: Prior to initiation of supplementation (if indicated)
Serum Phosphate
Rationale: To assess baseline phosphate levels. Not typically needed for routine 400 IU supplementation.
Timing: Prior to initiation of supplementation (if indicated)
Routine Monitoring
Serum 25-hydroxyvitamin D [25(OH)D]
Frequency: Not routinely needed for 400 IU daily dose in healthy individuals. If higher doses are used for deficiency, recheck 3-6 months after initiation.
Target: 30-100 ng/mL (75-250 nmol/L)
Action Threshold: Below 20 ng/mL (deficiency) or above 100 ng/mL (potential toxicity)
Serum Calcium
Frequency: Not routinely needed for 400 IU daily dose. If higher doses are used or patient has risk factors for hypercalcemia, recheck periodically (e.g., every 3-6 months).
Target: 8.5-10.2 mg/dL
Action Threshold: Above 10.5 mg/dL (hypercalcemia)
Serum Phosphate
Frequency: Not routinely needed for 400 IU daily dose. If higher doses are used or patient has risk factors, recheck periodically.
Target: 2.5-4.5 mg/dL
Action Threshold: Above 4.5 mg/dL (hyperphosphatemia)
Symptom Monitoring
- Symptoms of hypercalcemia: nausea, vomiting, constipation, polyuria, polydipsia, muscle weakness, fatigue, confusion, kidney stones.
Special Patient Groups
Pregnancy
Adequate vitamin D intake is crucial during pregnancy for maternal and fetal bone health. The recommended daily allowance (RDA) is 600 IU. Higher doses may be prescribed for deficiency under medical supervision. Excessive doses should be avoided.
Trimester-Specific Risks:
First Trimester:
Adequate intake important for early fetal development.
Second Trimester:
Continued importance for fetal bone mineralization.
Third Trimester:
Crucial for fetal bone mineralization and maternal vitamin D stores.
Lactation
Adequate vitamin D intake is important for lactating mothers. The RDA is 600 IU. Vitamin D is excreted in breast milk, but usually in small amounts. Supplementation of the infant (400 IU daily) is often recommended for breastfed infants.
Infant Risk:
L1 (safest) when taken within recommended doses. No known adverse effects on breastfed infants with maternal intake of recommended doses. High maternal doses could theoretically lead to infant hypercalcemia, but this is rare.
Pediatric Use
Essential for bone growth and development, prevention of rickets. Infants (especially breastfed) require supplementation. Dosing varies by age group (see detailed dosing).
Geriatric Use
Older adults are at higher risk for vitamin D deficiency due to decreased skin synthesis, reduced dietary intake, and potential malabsorption. Supplementation is often recommended, with some guidelines suggesting higher daily intake (e.g., 800 IU) for bone health.
Clinical Information
Clinical Pearls
- Cholecalciferol (Vitamin D3) is generally preferred over ergocalciferol (Vitamin D2) as it is more potent and effective at raising serum 25(OH)D levels.
- Vitamin D is fat-soluble; taking it with a meal containing fat significantly improves absorption.
- While 400 IU is a common maintenance dose, many individuals, especially those with limited sun exposure or certain medical conditions, may require higher doses to achieve optimal vitamin D levels.
- Routine monitoring of 25(OH)D levels is generally not necessary for healthy individuals taking 400 IU daily, but it is crucial when treating deficiency with higher doses.
- Symptoms of hypercalcemia (due to excessive vitamin D intake) can be subtle and include fatigue, nausea, and constipation. Prompt recognition is important.
Alternative Therapies
- Ergocalciferol (Vitamin D2)
- Calcitriol (active form, used in severe renal disease)
- Sun exposure (natural production)
Cost & Coverage
Average Cost:
$5 - $20 per 30 tablets
Generic Available:
Yes
Insurance Coverage:
Often OTC, generally not covered by prescription drug plans unless specifically prescribed for a medical condition (e.g., severe deficiency) and a prescription strength is used.
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.