Desmopressin is a man-made form of a hormone that occurs naturally in the pituitary gland. This hormone is important for many functions including blood flow, blood pressure, kidney function, and regulating how the body uses water.

Desmopressin injection is used to treat bleeding episodes in people with hemophilia A or von Willebrand's disease Type I.

Desmopressin injection is also used to treat central cranial diabetes insipidus, and increased thirst and urination caused by head surgery or head trauma.

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

You should not use this medication if you have severe kidney disease or if you have ever had hyponatremia (low sodium levels in your body).

You may not be able to use desmopressin if you have uncontrolled high blood pressure, severe heart failure, severe kidney disease, a condition called SIADH (syndrome of inappropriate antidiuretic hormone secretion), or any condition that causes excessive thirst, dehydration, or an electrolyte imbalance.

Call your doctor right away if you have signs of low sodium: headache, confusion, muscle cramps, severe weakness, vomiting, loss of coordination, and feeling restless or unsteady.

Limit your intake of water and other fluids while you are using desmopressin. Drinking too much water can cause your body to lose sodium, which may lead to a serious, life-threatening electrolyte imbalance.

Your doctor may perform blood tests to make sure you do not have conditions that would prevent you from safely using desmopressin.

Follow all directions on your prescription label. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Desmopressin is injected under the skin, or into a vein through an IV. You may be shown how to use injections at home. Do not give yourself this medicine if you do not understand how to use the injection and properly dispose of needles, IV tubing, and other items used.

Desmopressin is also available as a nasal spray. If you were switched from desmopressin nasal to desmopressin injection, your dosage needs will change. The desmopressin injection dose is much lower than the desmopressin nasal dose. Follow your doctor's dosing instructions very carefully.

While using desmopressin, your blood pressure will need to be checked often and you may need frequent blood tests.

Limit your intake of water and other fluids while you are using desmopressin. Drinking too much water can cause your body to lose sodium, which may lead to a serious, life-threatening electrolyte imbalance.

Fluid restriction is especially important in children and older adults using desmopressin. Follow your doctor's instructions about the type and amount of liquids you should drink.

Prepare your dose only when you are ready to give an injection. Do not use if the medicine has changed colors or has particles in it. Call your pharmacist for new medicine.

Use a disposable needle and syringe only once. Follow any state or local laws about throwing away used needles and syringes. Use a puncture-proof "sharps" disposal container (ask your pharmacist where to get one and how to throw it away). Keep this container out of the reach of children and pets.

If you are treating hemophilia or von Willebrand's disease, get medical attention if your bleeding is not controlled during treatment with desmopressin.

Store this medicine in the refrigerator. Do not freeze.

You should not use desmopressin if you are allergic to desmopressin, or if you have:

• severe kidney disease; or

• if you have ever had hyponatremia (low sodium levels in your body).

To make sure desmopressin is safe for you, tell your doctor if you have:

• an electrolyte imbalance;

• a psychologic disorder that causes extreme or unusual thirst;

• fluid retention;

• congestive heart failure, coronary artery disease;

• high or low blood pressure;

• urination problems;

• kidney disease;

• cystic fibrosis;

• a head injury or brain tumor; or

• a history of blood clots, stroke, or heart attack.

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It is not known whether desmopressin passes into breast milk or if it could affect the nursing baby. Tell your doctor if you are breast-feeding.

Use the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not use extra medicine to make up the missed dose.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include headache, confusion, drowsiness, rapid weight gain, or urination problems.

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

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

Desmopressin may cause serious side effects. Call your doctor at once if you have:

• low levels of sodium in the body--headache, confusion, hallucinations, muscle cramps, severe weakness, vomiting, loss of coordination, feeling restless or unsteady;

• a seizure (convulsions);

• weak or shallow breathing; or

• a light-headed feeling, like you might pass out.

Common side effects of desmopressin may include:

• pain, redness, burning, or swelling where the medicine was injected;

• flushing (warmth, redness, or tingly feeling);

• headache; or

• nausea, stomach pain.

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.

Tell your doctor about all your current medicines and any you start or stop using, especially:

• an antidepressant;

• a diuretic or "water pill";

• narcotic pain medicine;

• seizure medicine--carbamazepine, lamotrigine; or

• NSAIDs (nonsteroidal anti-inflammatory drugs)--aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve), celecoxib, diclofenac, indomethacin, meloxicam, and others.

This list is not complete. Other drugs may interact with desmopressin, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.