Desmopressin is used to control the amount of urine your kidneys make. Normally, the amount of urine you make is controlled by a certain substance in the body called vasopressin. In people who have "water diabetes" (diabetes insipidus) or certain kinds of head injury or brain surgery, the body does not make enough vasopressin. Desmopressin is a man-made form of vasopressin and is used to replace a low level of vasopressin. This medication helps to control increased thirst and too much urination due to these conditions, and helps prevent dehydration.

Desmopressin is also used to control bleeding caused by surgery or injuries in people with certain bleeding problems (hemophilia A, type 1 von Willebrand's disease). It works by helping the body with normal blood clotting.

When this medication is used to control bleeding, it is given by injection into a vein by a health care professional. It is given as directed by your doctor, usually over 15 to 30 minutes.

When this medication is used to control increased thirst and too much urination, it is given by injection into a vein or under the skin as directed by your doctor, usually twice a day.

The dosage is based on your medical condition and response to treatment. Do not use more desmopressin or use it more often than prescribed.

If you are using this medication at home, learn all preparation and usage instructions from your health care professional. Before using, check this product for particles or discoloration. If either is present, do not use the liquid. Learn how to store and discard medical supplies safely.

Use this medication regularly to get the most benefit from it. To help you remember, use it at the same times each day.

Limit drinking of water and other fluids while using this medication, especially in children and older adults. Consult your doctor for details. If you find that you are drinking more fluids than directed, tell your doctor right away. Your treatment will need to be adjusted.

Tell your doctor if your condition does not get better or if this medication stops working well.

See also Warning section.

Headache, nausea, upset stomach, flushing of the face, or redness/pain/swelling at the injection site may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Rarely, desmopressin may affect your blood pressure. It may cause an increase or decrease in your blood pressure. A temporary drop in your blood pressure may result in dizziness and a fast heartbeat. Ask your doctor for more details, especially if you have heart problems or high or low blood pressure. Tell your doctor promptly if changes in your blood pressure occur or if any of these symptoms occur.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before using desmopressin, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• kidney disease
• high or low blood pressure
• heart problems (such as blocked blood vessels, heart failure)
• conditions that may increase your risk of fluid/mineral imbalance (such as cystic fibrosis)
• the urge to drink too much water without being thirsty
• a low level of sodium in the blood (hyponatremia)
• history of blood clots

If you become dehydrated, your doctor will correct that condition first before starting treatment with desmopressin.

This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis). Alcohol can also interfere with how well desmopressin works.

Tell the doctor right away if you develop any illness that can cause water/mineral imbalance (including fever, diarrhea, vomiting, infections such as the flu) or if you experience conditions that require drinking more fluids (for example, exposure to very hot weather, strenuous exercise, heavy sweating). The doctor may need to stop or adjust desmopressin treatment, especially in children and older adults.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Children may be more sensitive to the side effects of this drug, especially water/mineral imbalance and a low level of sodium in the blood.

Older adults may be at greater risk for water/mineral imbalance and a low level of sodium in the blood while using this drug.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

This medication passes into breast milk. Consult your doctor before breastfeeding.

See also Warning section.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug are:

• corticosteroids that are taken by mouth or inhaled (such as fluticasone, prednisone)
• tolvaptan
• "water pills"/diuretics (such as furosemide)

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669. Symptoms of overdose may include: headache that is severe or doesn't go away, confusion, drowsiness, sudden weight gain.

Do not share this medication with others.

Lab and/or medical tests (such as urine tests, sodium blood level, blood pressure, pulse) may be done while you are using this medication. Keep all medical and lab appointments. Consult your doctor for more details.

If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Use your next dose at the regular time. Do not double the dose to catch up.

Store in the refrigerator. Do not freeze. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.