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Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.





This medication is used to treat a type of high blood pressure in the lungs (pulmonary hypertension). It works by causing the blood vessels (arteries) in the lungs to relax and expand, thus decreasing the pressure.

How To Use

Inject this medication directly into a vein (IV) continuously, using an infusion pump, or use as directed by your doctor. This medication should be started in a hospital/clinic. Do not suddenly decrease the dose or stop using this medication, unless directed to do so by your doctor. Stopping this drug, even briefly, may lead to serious side effects (see Side Effects section). To avoid interruptions in drug treatment, you should have access to a backup infusion pump and infusion sets should your equipment fail. Consult your doctor or pharmacist for more information. Depending on your condition, you may be given other medications to help prevent blood clots (embolism). Take all prescribed medication exactly as directed. Learn all preparation and usage instructions, including how to prepare and administer this drug and how to care for the injection site (central venous catheter) and avoid infection. If any of the information about the use of this medication is unclear, consult your doctor or pharmacist. Follow all instructions for proper mixing and dilution with correct IV fluids. Learn how to store and discard needles and medical supplies safely. If you have questions regarding the use of this medication, consult your pharmacist. Before using, check this product visually for particles or discoloration. If either is present, do not use the liquid.

Side Effects

Nausea, headache, vomiting, loss of appetite, diarrhea, dizziness, jaw pain, flushing, sweating, drowsiness, joint/muscle aches, or redness/swelling/pain at the injection site may occur. If any of these effects persist or worsen, notify your doctor promptly. Tell your doctor immediately if any of these serious side effects occur: stomach pain, chest pain, vision changes, fast/slow/irregular pulse, mental/mood changes, changes in the appearance of the skin (e.g., unusual paleness or blue/grey color), signs of flu (e.g., chills, fever, sore throat), unusual bleeding or bruising, tingling /numbness/loss of feeling in hands or feet. Tell your doctor immediately if any of these unlikely but serious side effects occur: unusual fatigue or weakness, enlarged abdomen, unexplained weight gain/loss. An allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of an allergic reaction include: rash, itching, swelling, severe dizziness, trouble breathing. Do not suddenly stop using this medication or decrease the dose unless directed to do so by your doctor. Serious effects such as trouble breathing, dizziness, or weakness may occur, which rarely may lead to death, if this medication is suddenly stopped or interrupted even briefly. Contact your doctor or pharmacist immediately if your dose is interrupted or if you develop these side effects. If you notice other effects not listed above, contact your doctor or pharmacist.


This medication should not be used if you have the following medical conditions: certain types of congestive heart failure (left ventricular systolic dysfunction), certain lung problems (pulmonary edema). Tell your doctor your medical history, especially of: bleeding problems, liver disease, any allergies. This drug may make you dizzy or drowsy or cause changes in vision; use caution engaging in activities requiring alertness such as driving or operating machinery. Limit alcoholic beverages. This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor. It is not known whether this drug passes into breast milk. Consult your doctor before breast-feeding.

Drug Interactions

Tell your doctor of all prescription and nonprescription medication you may use, especially: "water pills" (e.g., furosemide, torsemide), "blood thinners" (e.g., warfarin, heparins), blood pressure medication (e.g., captopril, lisinopril, nifedipine), vasodilators (e.g., hydralazine, nitrates), digoxin. Also report any drugs that cause drowsiness, such as: medicine for sleep (sedatives), tranquilizers, anti-anxiety drugs (e.g., alprazolam, diazepam), narcotic pain relievers (codeine), psychiatric medicines (e.g., phenothiazines such as chlorpromazine or tricyclics such as amitriptyline), anti-seizure drugs (e.g., carbamazepine, phenobarbital), muscle relaxants, antihistamines that cause drowsiness (e.g., chlorpheniramine, diphenhydramine). Check the labels on all your medicines (e.g., cough-and-cold products) because they may contain drowsiness-causing ingredients. Ask your pharmacist about the safe use of those products. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include: severe dizziness, loss of consciousness.


Do not share this medication with others. Laboratory and/or medical tests (e.g., blood pressure, heart rate, heart function) will be performed to monitor your progress and response to this medication.

Missed Dose

This drug is to be given continuously into a vein. If your dose is interrupted, contact your doctor or pharmacist immediately to establish new dosing.


Store unopened vials at room temperature between 59 and 77 degrees F (15 to 25 degrees C) away from light and moisture. Do not freeze. Consult your pharmacist for details regarding the stability of the drug after dilution in correct IV fluids. Discard any unused fluid.

Medical Alert

Your condition can cause complications in a medical emergency. For enrollment information call MedicAlert at 1-800-854-1166 (USA), or 1-800-668-1507 (Canada).