Ergocalciferol is vitamin D2. Vitamin D helps your body absorb calcium.

Ergocalciferol is used to treat hypoparathyroidism (decreased functioning of the parathyroid glands).

Ergocalciferol is also used to treat rickets (softening of the bones caused by vitamin D deficiency) or low levels of phosphate in the blood (hypophosphatemia).

Ergocalciferol may also be used for purposes not listed in this medication guide.

You should not take ergocalciferol if you have had an allergic reaction to vitamin D, or if you have high levels of calcium or vitamin D in your body, or any condition that makes it hard for your body to absorb nutrients from food (malabsorption).

Use only the recommended dose of ergocalciferol. An overdose could cause serious or life-threatening side effects.

Ergocalciferol comes as a capsule to take by mouth. It is usually taken once daily. Take ergocalciferol at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take ergocalciferol exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the capsules whole; do not chew or crush them.

Your doctor may change your dose depending on your body's response to ergocalciferol.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use only the recommended dose of ergocalciferol.

It may be best to take ergocalciferol after a meal, but you may take ergocalciferol with or without food.

Measure liquid medicine carefully. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

You will need frequent medical tests.

Your doctor may begin to reduce your ergocalciferol dose as your condition improves. Carefully follow all instructions about adjusting your dose. In some cases, there may be a very small difference in amount between safe and dangerous doses of this medicine.

Your doctor will determine how long to treat you with this medicine.

Ergocalciferol may be only part of a complete program of treatment that also includes dietary changes and taking calcium and vitamin supplements. Follow your doctor's instructions very closely.

Learn about the foods you should eat to make sure you get enough calcium and vitamin D in your diet. Your ergocalciferol dose may need to be adjusted as you make changes to your diet.

Store at room temperature away from moisture, heat, and light.

You should not take ergocalciferol if you have had an allergic reaction to vitamin D, or if you have:

• high levels of vitamin D in your body (hypervitaminosis D);

• high levels of calcium in your blood (hypercalcemia); or

• any condition that makes it hard for your body to absorb nutrients from food (malabsorption).

Tell your doctor if you have ever had:

• heart disease;

• kidney disease; or

• an electrolyte imbalance.

Certain forms of ergocalciferol may contain ingredients you should know about, such as peanut or soybean oil, sugar, aspartame (phenylalanine), or certain food dyes. Ask a doctor before using ergocalciferol if you have allergies, diabetes, or phenylketonuria (PKU).

Too much vitamin D could harm an unborn baby, and your dose needs may be different during pregnancy. Tell your doctor if you are pregnant or if you become pregnant while taking ergocalciferol.

Ergocalciferol can pass into breast milk and may cause side effects in the nursing baby. Tell your doctor if you are breast-feeding.

Do not give ergocalciferol to a child without medical advice. Your child's dose will depend on age, weight, diet, and other factors.

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of vitamin D can cause serious or life-threatening side effects.

Overdose symptoms may include nausea, loss of appetite, thirst, urinating more or less than usual, body aches, stiffness, confusion, or irregular heartbeats.

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from light, excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

Ergocalciferol will work only if you also get the right amount of calcium from the foods you eat. If you get too much calcium from foods, you may experience serious side effects from taking ergocalciferol. If you do not get enough calcium from foods, ergocalciferol will not control your condition. Your doctor will tell you which foods are good sources of calcium and how many servings you need each day. If you find it difficult to eat enough of these foods, tell your doctor. In that case, your doctor can prescribe or recommend a calcium supplement.

Your doctor may also prescribe a low-phosphate diet during your treatment with ergocalciferol. Follow these directions carefully.

Ask a doctor or pharmacist before taking any multivitamins, mineral supplements, or antacids while you are taking ergocalciferol.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop taking ergocalciferol and call your doctor at once if you have:

• chest pain, feeling short of breath;

• growth problems (in a child taking ergocalciferol); or

• early signs of vitamin D overdose--weakness, metallic taste in your mouth, weight loss, muscle or bone pain, constipation, nausea, and vomiting.

Less serious side effects may be more likely, and you may have none at all.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Certain medications can make it harder for your body to absorb vitamin D. If you take other medications, take them at least 2 hours before or 2 hours after you take ergocalciferol.

Tell your doctor about all your other medicines, especially:

• a diuretic or "water pill"; or

• mineral oil (sometimes taken as a laxative).

This list is not complete. Other drugs may affect ergocalciferol, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests before and during your treatment with ergocalciferol.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.