Loading...
Loading...
Medical Disclaimer: This information is for educational purposes only and is not a substitute for professional medical advice.
Ergocalciferol (vitamin D2)
Brand Name
Ergocalciferol (vitamin D2)
Generic Name
Ergocalciferol (vitamin D2)
Active Ingredient
ErgocalciferolCategory
Provitamin D2 Compound [EPC]
Variants
1
Different strengths and dosage forms
| Strength | Form | Route | NDC |
|---|---|---|---|
| 1.25 mg/1 | CAPSULE | ORAL | 80425-0130 |
Detailed information about Ergocalciferol (vitamin D2)
References used for this content
This page is for informational purposes only and does not replace medical advice. Before using any prescription or over-the-counter medication for Ergocalciferol (vitamin D2), you must consult a qualified healthcare professional.
Ergocalciferol, also known as Vitamin D2, is a fat-soluble vitamin used to treat hypoparathyroidism, refractory rickets, and familial hypophosphatemia. It belongs to the class of Vitamin D analogs and is essential for calcium and phosphate homeostasis.
The dosage of ergocalciferol is highly individualized based on the patient’s serum calcium levels and the specific condition being treated.
Ergocalciferol is used in children to treat rickets and other metabolic bone disorders, but the dosage must be carefully calculated by a pediatrician.
Patients with chronic kidney disease (CKD) often have a deficiency in the enzyme 1-alpha-hydroxylase. Consequently, they may not respond to ergocalciferol and may instead require "active" Vitamin D analogs like calcitriol. However, in early stages of CKD, ergocalciferol may still be used under close supervision.
Since the first step of activation occurs in the liver, patients with severe liver disease (e.g., cirrhosis) may have a reduced ability to convert ergocalciferol into its 25-hydroxy form. Dosage adjustments or the use of pre-hydroxylated analogs may be necessary.
Older adults are at a higher risk for Vitamin D deficiency due to reduced skin synthesis and dietary changes. While standard doses are generally safe, healthcare providers must monitor renal function closely, as the risk of hypercalcemia (high blood calcium) may be higher in this population.
If you miss a dose of ergocalciferol, take it as soon as you remember. However, if it is almost time for your next scheduled dose, skip the missed dose and return to your regular schedule. Do not take two doses at once to make up for a missed one. If you are on a weekly schedule and miss a dose by several days, consult your healthcare provider for guidance.
An overdose of ergocalciferol leads to hypervitaminosis D, which results in dangerously high levels of calcium in the blood (hypercalcemia). Signs of overdose include:
In the event of a suspected overdose, seek emergency medical attention immediately. Treatment typically involves stopping the medication, intravenous hydration, and sometimes the use of medications like corticosteroids or bisphosphonates to lower calcium levels.
> Important: Follow your healthcare provider's dosing instructions. Do not adjust your dose without medical guidance, as Vitamin D can be toxic in high amounts.
When taken at recommended nutritional doses, ergocalciferol rarely causes side effects. However, at the high therapeutic doses used for medical conditions, some patients may experience:
These symptoms are often early indicators that calcium levels are beginning to rise and should be reported to a doctor.
> Warning: Stop taking Ergocalciferol and call your doctor immediately if you experience any of these symptoms of hypercalcemia (high calcium levels):
Prolonged use of high-dose ergocalciferol without proper monitoring can lead to chronic hypercalcemia, which has several serious long-term consequences:
There are currently no FDA black box warnings for Ergocalciferol. However, the FDA emphasizes that the therapeutic index is narrow—meaning the difference between a safe dose and a toxic dose can be small in certain patients. Therefore, the medication must be used under strict medical supervision with regular lab work.
Report any unusual symptoms to your healthcare provider. Monitoring your calcium and Vitamin D levels is the best way to prevent these side effects.
Ergocalciferol is a potent medication that significantly alters mineral metabolism. It should never be used as a general supplement without a confirmed medical need and a prescription from a healthcare provider. The most critical safety concern is the prevention of Vitamin D toxicity, which can be life-threatening if left untreated. Patients must be educated on the signs of high calcium and the importance of adhering to the prescribed dose.
No FDA black box warnings for Ergocalciferol. Unlike some medications that carry severe risks of liver failure or suicidal ideation, the primary risk with ergocalciferol is metabolic imbalance (hypercalcemia).
When taking therapeutic doses of ergocalciferol, your healthcare provider will require regular laboratory testing. This typically includes:
Ergocalciferol generally does not interfere with the ability to drive or operate machinery. However, if you experience symptoms of hypercalcemia, such as extreme fatigue, dizziness, or mental confusion, you should avoid these activities and contact your doctor immediately.
While there is no direct chemical interaction between ergocalciferol and alcohol, chronic excessive alcohol consumption can interfere with the liver's ability to metabolize Vitamin D and can also impair the absorption of nutrients in the gut. It is best to discuss your alcohol intake with your doctor to ensure it does not complicate your treatment.
Ergocalciferol does not cause a withdrawal syndrome and does not typically require tapering. However, if you stop taking it suddenly, your Vitamin D and calcium levels will eventually fall, which could lead to a recurrence of your original symptoms (e.g., bone pain or muscle tetany). Always consult your doctor before stopping the medication.
> Important: Discuss all your medical conditions, especially kidney disease or heart problems, with your healthcare provider before starting Ergocalciferol.
There are few absolute contraindications, but ergocalciferol should generally not be used with other high-dose Vitamin D analogs (like calcitriol or doxercalciferol) unless specifically directed by a specialist. The primary risk is an additive effect leading to rapid, severe hypercalcemia.
Ergocalciferol can affect the results of certain laboratory tests:
> Important: Tell your doctor about ALL medications, supplements, and herbal products you are taking. A complete list helps prevent dangerous metabolic imbalances.
Ergocalciferol must NEVER be used in the following circumstances:
In these conditions, the use of ergocalciferol requires a careful risk-benefit analysis and intensive monitoring:
There is no known cross-sensitivity between ergocalciferol and unrelated drug classes. However, patients who have had an allergic reaction to cholecalciferol (Vitamin D3) or other Vitamin D analogs (like calcitriol) should be monitored closely for signs of hypersensitivity, such as rash or swelling, although true allergies to Vitamin D are exceedingly rare.
> Important: Your healthcare provider will evaluate your complete medical history, including your kidney function and current calcium levels, before prescribing Ergocalciferol.
Ergocalciferol is classified by the FDA as Pregnancy Category C (in doses exceeding the Recommended Dietary Allowance). This means that while animal studies have shown some risks, there are no adequate and well-controlled studies in pregnant women.
Vitamin D and its metabolites are excreted in human breast milk.
Ergocalciferol is widely used to treat rickets and hypoparathyroidism in children.
Patients over the age of 65 are frequently prescribed Vitamin D to prevent falls and fractures.
In patients with mild to moderate renal impairment, ergocalciferol can be used but requires frequent monitoring of the calcium-phosphorus product (the serum calcium multiplied by the serum phosphorus). If this product exceeds 55 mg²/dL², there is a high risk of calcification in soft tissues. Patients with end-stage renal disease (ESRD) typically do not benefit from ergocalciferol because their kidneys cannot activate it; they usually require calcitriol instead.
Patients with biliary cirrhosis or other forms of obstructive jaundice will have difficulty absorbing ergocalciferol due to a lack of bile salts. For these patients, an injectable form or a water-miscible oral preparation may be necessary. Liver function tests (LFTs) should be monitored to ensure the first step of Vitamin D activation is occurring effectively.
> Important: Special populations require individualized medical assessment and frequent laboratory follow-ups to ensure safety.
Ergocalciferol (Vitamin D2) is a secosteroid. Its primary molecular mechanism involves the activation of the Vitamin D Receptor (VDR), a member of the nuclear receptor superfamily.
| Parameter | Value |
|---|---|
| Bioavailability | ~60-80% (dependent on dietary fat) |
| Protein Binding | >99% (bound to Vitamin D-binding protein) |
| Half-life | 2-3 weeks (circulating 25-OH form) |
| Tmax | 12-24 hours |
| Metabolism | Hepatic (25-hydroxylation) and Renal (1-alpha-hydroxylation) |
| Excretion | Fecal (>95%), Renal (<5%) |
Ergocalciferol belongs to the therapeutic class of Vitamin D Analogs. It is specifically a Provitamin D2 compound. Related medications include cholecalciferol (D3), calcitriol (active D3), and paricalcitol (a synthetic analog used in kidney disease).
Common questions about Ergocalciferol (vitamin D2)
Ergocalciferol, also known as Vitamin D2, is primarily used to treat and prevent conditions caused by a lack of Vitamin D, such as rickets and osteomalacia. It is also a core treatment for hypoparathyroidism, a condition where the body does not produce enough parathyroid hormone, leading to low calcium levels. Additionally, healthcare providers prescribe high-dose ergocalciferol to manage familial hypophosphatemia, a genetic disorder affecting phosphate levels. In many cases, it is used to treat severe Vitamin D deficiency in adults who have malabsorption issues. Your doctor will determine the appropriate use based on your specific blood work and medical history.
Most people do not experience side effects when taking ergocalciferol at standard doses. However, at higher medical doses, common side effects can include constipation, dry mouth, a metallic taste in the mouth, and a loss of appetite. These are often early signs that your calcium levels are becoming too high. Some patients may also feel unusually tired or experience mild nausea. If these symptoms persist or become bothersome, it is important to contact your healthcare provider. They may need to adjust your dose or check your blood calcium levels.
There is no known direct chemical interaction between ergocalciferol and alcohol. However, chronic and excessive alcohol consumption can interfere with the liver's ability to process Vitamin D and can also damage the lining of the gut, making it harder for your body to absorb fat-soluble vitamins. Alcohol can also contribute to bone loss over time, which may counteract the benefits of the medication. For these reasons, it is generally recommended to limit alcohol intake while being treated for Vitamin D deficiency or bone disorders. Always discuss your lifestyle habits with your doctor to ensure the best treatment outcomes.
Ergocalciferol should only be used during pregnancy if the potential benefit justifies the potential risk to the fetus. While standard doses found in prenatal vitamins are considered safe and necessary, very high therapeutic doses (like 50,000 IU) are categorized as Pregnancy Category C. Animal studies have suggested that extremely high levels of Vitamin D can lead to birth defects, particularly heart-related issues. However, untreated Vitamin D deficiency also poses risks to both the mother and the baby, such as preeclampsia. Your obstetrician will monitor your levels closely and prescribe the lowest effective dose if treatment is required.
The time it takes for ergocalciferol to work depends on the condition being treated and the goals of therapy. For increasing intestinal calcium absorption, the effects typically begin within 12 to 24 hours after the first dose. However, if you are taking it to correct a severe deficiency or to treat bone diseases like rickets, it may take several weeks or even months of consistent use to see significant changes in blood levels and bone density. Your doctor will likely re-test your Vitamin D and calcium levels after 8 to 12 weeks of treatment to assess how well the medication is working for you.
You can generally stop taking ergocalciferol without experiencing immediate withdrawal symptoms because it is a vitamin that the body stores in fat tissues. However, stopping the medication suddenly without a doctor's guidance can lead to a gradual return of Vitamin D deficiency and its associated symptoms, such as bone pain, muscle weakness, or low blood calcium. If you are taking it for a chronic condition like hypoparathyroidism, stopping it could lead to a dangerous drop in calcium levels very quickly. Always consult your healthcare provider before making any changes to your medication regimen.
If you miss a dose of ergocalciferol, take it as soon as you remember. If it is almost time for your next scheduled dose, skip the missed dose and continue with your regular schedule. You should never take a double dose to make up for a missed one, as this increases the risk of Vitamin D toxicity and high calcium levels. If you are on a once-weekly dosing schedule and you forget your dose by more than a few days, it is a good idea to call your pharmacist or doctor for specific instructions. Keeping a medication log or using a phone reminder can help you stay on track.
Ergocalciferol is not known to cause weight gain. In fact, one of the symptoms of taking too much Vitamin D (toxicity) is actually weight loss due to a loss of appetite and nausea. Some studies have looked into the relationship between Vitamin D and weight management, suggesting that maintaining adequate Vitamin D levels might actually support a healthy metabolism, but ergocalciferol itself is not a weight-loss or weight-gain drug. If you notice significant or unexplained changes in your weight while taking this medication, you should discuss them with your healthcare provider to rule out other underlying causes.
Ergocalciferol can interact with several other medications, so it is vital to provide your doctor with a full list of what you take. It can interact with certain diuretics (water pills), heart medications like digoxin, and anti-seizure drugs like phenytoin. Some weight-loss drugs and cholesterol medications can also prevent your body from absorbing Vitamin D correctly. Additionally, taking over-the-counter calcium supplements or antacids without supervision can lead to dangerously high calcium levels when combined with ergocalciferol. Your doctor will check for these interactions to ensure your treatment is both safe and effective.
Yes, ergocalciferol is widely available as a generic medication, which is typically much more affordable than brand-name versions like Drisdol. The generic versions are FDA-approved and are required to meet the same standards of safety, strength, and quality as the brand-name drug. It is available in various strengths, most commonly the 50,000 IU (1.25 mg) capsule used for intensive therapy. Because it is a prescription-strength vitamin, you will still need a valid prescription from a healthcare provider to obtain it from a pharmacy, even in its generic form.
Other drugs with the same active ingredient (Ergocalciferol)