Pitressin (Injection)

Vasopressin injection is used to manage frequent urination, increased thirst, and loss of water caused by diabetes insipidus. This condition leads the body to lose too much water and become dehydrated. Vasopressin injection is also used to prevent and treat swelling in the abdomen or stomach that can happen after surgery. It is also used in abdominal or stomach roentgenography.

Vasopressin injection is also used to raise blood pressure in adults with vasodilatory shock (for example, after heart surgery or due to sepsis) who still have low blood pressure after receiving fluids and medications.

Vasopressin is a hormone made by the body. It works on the kidneys to decrease urine production.

This medicine is available only with your doctor's prescription.

It is very important that your doctor monitors you closely while you are taking this medicine. This will help your doctor see if the medicine is working properly and to decide if you should keep using it. Blood and urine tests may be needed to check for unwanted effects.

Vasopressin may cause allergic reactions, including anaphylaxis. Anaphylaxis can be life-threatening and needs immediate medical attention. Call your doctor right away if you have a rash, itching, trouble breathing, trouble swallowing, or any swelling of your hands, face, or mouth while you are using this medicine.

This medicine may cause reversible diabetes insipidus. Tell your doctor right away if you have an increase in urine output, dilute urine, dizziness, fast heartbeat, high blood pressure, irritability, restlessness, seizures, or swelling of the feet or lower legs.

Do not take other medicines unless you have talked about them with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

In deciding to use a medicine, you and your doctor must consider the risks of taking it against the benefits it may provide. Here are some important points to think about:

Allergies

Inform your doctor if you have ever had any unusual or allergic reactions to this medicine or any other medications. Also, let your healthcare professional know about any other allergies you have, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

There have not been enough studies on the effects of Vasostrict® in children with vasodilatory shock. Safety and effectiveness have not been established.

Studies conducted so far have not shown any pediatric-specific issues that would limit the use of Pitressin® in children with diabetes insipidus and abdominal distension.

Geriatric

While appropriate studies on the effects of Vasostrict® in older adults have not been conducted, no specific problems related to age have been documented. However, older patients are more likely to have age-related kidney, liver, or heart issues, which may require caution and dose adjustments when using Vasostrict®.

There is no available information on the effects of Pitressin® in older patients.

Breast Feeding

There are not enough studies in women to determine the risk to infants when using this medication during breastfeeding. Consider the potential benefits and risks before using this medication while breastfeeding.

Interactions with Medicines

Some medicines should not be used together at all, while others may be used together even if an interaction could happen. In such cases, your doctor may want to adjust the dose, or take other precautions. When you are taking this medicine, it is very important for your healthcare professional to know if you are taking any of the medicines listed below. The following interactions are significant and not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to prescribe this medication or change some of the other medicines you take.

• Dihydroergotamine

Using this medicine with any of the following medicines is usually not recommended, but may be necessary in some cases. If both medicines are prescribed, your doctor may adjust the dose or how often you use one or both medicines.

• Ergonovine
• Indomethacin
• Methylergonovine

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be taken around the time of eating food or certain types of food due to potential interactions. Using alcohol or tobacco with certain medicines may also cause interactions. Talk to your healthcare professional about using your medicine with food, alcohol, or tobacco.

Other Medical Problems

Having other medical problems may affect the use of this medicine. Be sure to tell your doctor if you have any other medical conditions, especially:

• Asthma or
• Epilepsy or
• Heart disease or
• Heart failure or
• Migraine headaches—Use with caution. May worsen these conditions.

• Blood vessel disease or
• Coronary artery disease—Use with caution. May increase side effects.

• Chronic kidney disease (with nitrogen retention)—Should not be used in patients with this condition.

Along with its needed effects, this medicine may cause some unwanted effects. Not all of these side effects may occur, but if they do, they may need medical attention.

Check with your doctor right away if any of the following side effects occur:

Incidence not known

• Abdominal or stomach pain, usually after eating a meal
• agitation
• back pain
• chest pain or discomfort
• chest tightness or heaviness
• coma
• confusion
• constipation
• convulsions
• cough
• decreased urine output
• depression
• diarrhea
• difficulty with swallowing
• dilated neck veins
• dizziness
• extreme fatigue
• fainting
• fast or irregular heartbeat
• headache
• hives, itching, or rash
• hostility
• increased thirst
• irregular breathing
• irritability
• lethargy
• lightheadedness, dizziness, or fainting
• muscle pain or cramps
• muscle twitching
• nausea or vomiting
• no blood pressure or pulse
• pain in the shoulders, arms, jaw, or neck
• pale, cool, or blotchy skin on the arms or legs
• puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• rapid weight gain
• restlessness
• slow or irregular heartbeat
• stopping of heart
• stupor
• sweating
• swelling of the face, ankles, fingers, feet, or lower legs
• troubled breathing
• unconsciousness
• unusual tiredness or weakness
• weak or absent pulse in the arms or legs

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Your health care professional may also have ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue, are bothersome, or if you have any questions about them:

Incidence not known

• Abdominal or stomach cramps
• feeling of constant movement of self or surroundings
• pale skin
• passing of gas
• pounding in the head
• sensation of spinning
• shakiness in the legs, arms, hands, or feet
• sweating
• trembling or shaking of the hands or feet

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

In the U.S.

• Pitressin

Available Dosage Forms:

• Solution

Therapeutic Class: Endocrine-Metabolic Agent

Pharmacologic Class: Vasopressin (class)

A nurse or other trained health professional will give you this medicine in a hospital or clinic. This medicine is given as a shot under your skin, into a muscle or vein.

This medicine may be given at home to patients with diabetes insipidus who do not need to be in the hospital or clinic. If you are using this medicine at home, your doctor or nurse will teach you how to prepare and inject the medicine. Be sure that you understand how to use the medicine.

You will be shown the body areas where this shot can be given. Use a different body area each time you give yourself a shot. Keep track of where you give each shot to make sure you rotate body areas. This will help prevent skin problems from the injections.

Use a new needle and syringe each time you inject your medicine.

Your doctor may limit the amount of fluid or water you drink. Follow the instructions carefully to prevent unwanted effects.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For injection dosage form (solution): For treatment of diabetes insipidus: Adults and teenagers—5 to 10 Units injected into a muscle or under the skin 2 or 3 times a day as needed. Children—2.5 to 10 Units injected into a muscle or under the skin 3 or 4 times a day.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Throw away used needles in a hard, closed container that the needles cannot poke through. Keep this container away from children and pets.