Over-the-counter medication · Vitamin D2 Supplement
ergocalciferol
Also sold as Drisdol, Calciferol. This medicine treats conditions caused by low vitamin D levels.
Data updated 2026-05-15
- 366,491
- FDA reportsHeavily reported
- 1
- Recall record
What the data shows
ergocalciferol (Drisdol) is an over-the-counter Vitamin D2 Supplement, in the top 5% of tracked drugs by FAERS report volume (366,491 FDA reports).
Reporting volume reflects how widely a drug is used and studied, not how dangerous it is, a FAERS report documents a temporal association, never proof of cause.
ergocalciferol (Drisdol) is an over-the-counter Vitamin D2 Supplement. This medicine treats conditions caused by low vitamin D levels.
Ergocalciferol is a vitamin D2 supplement. It helps your body absorb calcium and phosphorus, which are important for strong bones.
Verify with FDA → · CMS NADAC pricing →
What it does
This medicine treats conditions caused by low vitamin D levels.
Common side effects
No common side effects listed.
Key warnings
The range between helpful and harmful doses is very small.
The sections below are summarized in plain English from ergocalciferol's FDA-approved prescribing information. They describe what the official label says, and are not personal medical advice.
How It Works
Ergocalciferol is a synthetic form of vitamin D2. It helps your body absorb calcium from the stomach and intestines. It also helps regulate calcium levels in your blood.
How to Take It
Take this medicine exactly as your doctor tells you. The dose will be based on your specific condition. You may need regular blood tests and X-rays while taking this medicine to monitor your progress. Make sure you get enough calcium in your diet.
This is a plain-language summary of ergocalciferol's FDA labeling, not individualized dosing advice. Ask a pharmacist or prescriber before changing how you take this medication.
Pregnancy & Breastfeeding
Tell your doctor if you are pregnant or breastfeeding. High doses of vitamin D during pregnancy can harm the baby. Talk to your doctor about the risks and benefits.
This is a plain-language summary of ergocalciferol's FDA labeling, not individualized advice. Ask a pharmacist or prescriber about pregnancy or breastfeeding on this medication.
Missed Dose
If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule.
This is a plain-language summary of ergocalciferol's FDA labeling, not individualized advice. Ask a pharmacist or prescriber what to do about your specific missed dose.
Storage
Store at room temperature (77°F), away from light and moisture.
Side Effects (from patient reports)
Based on 366,491 FDA adverse event reports.
Most-reported reactions
Adverse reactions in FAERS for ergocalciferol, by number of reports
- Tiredness
Tiredness
36,313 reports
- Feeling sick to your stomach
Feeling sick to your stomach
27,028 reports
- Loose stools
Loose stools
25,823 reports
- Head pain
Head pain
24,765 reports
- Pain
Pain
23,210 reports
- Difficulty breathing
Difficulty breathing
19,348 reports
- Joint pain
Joint pain
19,250 reports
- Feeling lightheaded
Feeling lightheaded
18,670 reports
- Weakness
Weakness
16,525 reports
- Accidental fall
Accidental fall
16,410 reports
What this shows Bars show how often each reaction was reported, not how likely it is to happen, a report records a temporal association, never proof that the drug caused it.
Reports over time
Adverse-event reports filed for ergocalciferol each year to the FDA Adverse Event Reporting System (FAERS).
Year-to-year volume tracks usage, prescribing, and scrutiny, not a change in per-patient risk. Source: FDA FAERS.
Where ergocalciferol sits
ergocalciferol has more FDA adverse-event reports than 98% of the drugs FAERS tracks. A high position reflects how widely a drug is used and watched, not how dangerous it is.
Percentile across all drugs PlainMeds tracks by FAERS report volume. The dot is ergocalciferol; the line is the median (50th percentile).
FDA Adverse Event Report Analysis
Detailed analysis of 366,491 reports from the FDA Adverse Event Reporting System (FAERS). Reports span 1999–2025.
Total Reports
366,491
Reports Mentioning Death
21,613
5.9% of reports — not proof of cause
Hospitalization Reports
98,409
Top Indication
Product Used For Unknown Indication
Gender Distribution
Age Distribution
Most Reported Adverse Reactions (FAERS)
| # | Reaction | Reports |
|---|---|---|
| 1 | FATIGUE | 36,312 |
| 2 | NAUSEA | 27,026 |
| 3 | DIARRHOEA | 25,824 |
| 4 | HEADACHE | 24,768 |
| 6 | PAIN | 23,207 |
| 8 | DYSPNOEA | 19,350 |
| 9 | ARTHRALGIA | 19,251 |
| 10 | DIZZINESS | 18,673 |
| 11 | ASTHENIA | 16,525 |
| 12 | FALL | 16,406 |
| 13 | VOMITING | 15,063 |
| 14 | PAIN IN EXTREMITY | 14,394 |
| 15 | MALAISE | 14,135 |
| 16 | RASH | 13,482 |
| 17 | PNEUMONIA | 12,872 |
Reactions in Death Reports
Reactions in Hospitalization Reports
Source: FDA FAERS (Adverse Event Reporting System) FDA FAERS (Adverse Event Reporting System) Reports are voluntary and do not establish causation
Serious Warnings
The range between helpful and harmful doses is very small. Your doctor needs to closely supervise your dosage. Too much vitamin D can cause serious side effects, including kidney problems and tissue damage.
Common Questions
What is the strength of each capsule?
How often will I need blood tests?
Can I take this with other medications?
What should I do if I experience side effects?
How will I know if the medicine is working?
Can I drink alcohol while taking this medicine?
What happens if I take too much?
Is there a generic version of this medicine?
How long will I need to take this medicine?
What should I avoid while taking this medicine?
What drug class is ergocalciferol?
Is ergocalciferol safe during pregnancy?
Has ergocalciferol been recalled?
Active Recalls
Defective Delivery System: Leakage observed after oral solution was repackaged into unit-dose syringes.
Safecor Health, LLC
Related Medications in Vitamin D2 Supplement
Other drugs grouped near ergocalciferol - same-class peers and common alternatives.
ascorbic acid
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Compare with ergocalciferol →
biotin
Vitamin B7
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calcitriol
Rocaltrol
Calcitriol is a form of vitamin D that helps your body absorb and use calcium.
Compare with ergocalciferol →
calcium carbonate
Tums, Caltrate
Calcium carbonate is a medicine that can relieve heartburn and upset stomach.
Compare with ergocalciferol →
cholecalciferol
Vitamin D3
PNV-DHA is a multivitamin with minerals and essential fatty acids.
Compare with ergocalciferol →
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What the FDA Data Shows for ergocalciferol
The FDA label for ergocalciferol (sold under brand names such as Drisdol, Calciferol) classifies it as an over-the-counter product in the Vitamin D2 Supplement class. This medicine treats conditions caused by low vitamin D levels. Labeling covers dosing, contraindications, and monitoring requirements derived from clinical trials.
Post-market surveillance from the FDA Adverse Event Reporting System (FAERS) captures real-world experience. For this drug, FAERS contains 366,491 voluntary reports. Interaction data is drawn directly from FDA-approved prescribing information. Acquisition-cost data is surveyed weekly by CMS and updated as manufacturers report changes.
Report counts do not establish causation, a FAERS entry documents a temporal association, not proof that the drug produced the outcome. Widely prescribed medications naturally accumulate more reports than niche therapies, so raw totals must be interpreted alongside total exposure. Shortage status, recall history (currently 1 recall record on file), and patent information further shape supply and switching decisions. This page summarizes public FDA data for educational purposes only and is not a substitute for professional medical advice, always consult a licensed healthcare provider before starting, stopping, or changing any medication.
Data Sources
Drug labeling: FDA Drug Labels (SPL/DailyMed). Adverse events: FDA Adverse Event Reporting System (FAERS).
FAERS reports are voluntary and do not establish causation. Drug interactions are derived from FDA labeling and clinical references. Always consult a healthcare professional before making medication decisions.
Last updated: January 31, 2025
Read our methodology - how this data is sourced, computed, and verified.
Data currency: FDA FAERS adverse-event reports through 2025, CMS NADAC acquisition-cost pricing effective December 2024, compiled and last refreshed May 2026. See our methodology for per-source dates and refresh cadence. Spot a figure that looks wrong? Report a correction.
All federal data sources used on this page
- FDA Orange Book - approved drug products with therapeutic equivalence. accessdata.fda.gov/cder/ob
- FDA DailyMed - NIH-hosted drug labeling for FDA-approved meds. dailymed.nlm.nih.gov
- FDA Adverse Event Reporting System (FAERS) - post-marketing safety surveillance. fda.gov/drugs/faers
- NLM RxNorm - standardized clinical drug nomenclature. nlm.nih.gov/research/umls/rxnorm
- CMS Medicare Part B Drug Average Sales Price Files - federal drug pricing data. cms.gov/medicare/part-b-drugs/asp
- FDA Drug Shortages Database - current and resolved drug shortage tracking. accessdata.fda.gov/drugshortages