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Premarin Intravenous

Generic name: conjugated estrogens

What is Premarin Intravenous?

Premarin Intravenous is a medicine that contains a mixture of estrogen hormones.

Premarin Intravenous is used to:

  • Treat certain types of abnormal uterine bleeding due to hormonal imbalance when your doctor has found no other cause of bleeding

What is the most important information I should know about Premarin Intravenous?

  • Using estrogen-alone increases your chance of getting cancer of the uterus (womb)
    Report any unusual vaginal bleeding right away. Vaginal bleeding after menopause may be a warning sign of cancer of the uterus (womb). Your healthcare provider should check any unusual vaginal bleeding to find out the cause.
  • Do not use estrogen-alone to prevent heart disease, heart attacks, strokes, or dementia (decline in brain function)
  • Using estrogen-alone may increase your chances of getting stroke or blood clots
  • Using estrogen-alone may increase your chance of getting dementia, based on a study of women 65 years of age or older
  • Do not use estrogens with progestins to prevent heart disease, heart attacks, strokes or dementia
  • Using estrogens with progestins may increase your chances of getting heart attacks, strokes, breast cancer, or blood clots
  • Using estrogens with progestins may increase your chance of getting dementia, based on a study of women 65 years of age or older
  • You and your healthcare provider should talk regularly about whether you still need treatment with estrogens

Who should not use Premarin Intravenous?

Premarin Intravenous should not be used if you:

  • Have unusual vaginal bleeding that has not been evaluated by your healthcare provider
  • Currently have or have had certain cancers
    Estrogens may increase the chance of getting certain types of cancers, including cancer of the breast or uterus. If you have or have had cancer, talk with your healthcare provider about whether you should use Premarin Intravenous.
  • Had a stroke or heart attack
  • Currently have or have had blood clots
  • Currently have or have had liver problems
  • Have been diagnosed with a bleeding disorder
  • Are allergic to Premarin Intravenous or any of its ingredients
    See the list of ingredients in Premarin Intravenous at the end of this guide.
  • Think you may be pregnant

What should I tell my healthcare provider before using Premarin Intravenous?

Tell your healthcare provider:

  • If you are breast feeding
    • The hormones in Premarin Intravenous can pass into your breast milk.
  • About all of your medical problems
    • Your healthcare provider may need to check you more carefully if you have certain conditions, such as asthma (wheezing), epilepsy (seizures), diabetes, migraine, endometriosis, lupus, problems with your heart, liver, thyroid, kidneys, or have high calcium levels in your blood.
  • About all the medicines you take
    • This includes prescription and nonprescription medicines, vitamins, and herbal supplements. Some medicines may affect how Premarin Intravenous works.

How should I take Premarin Intravenous?

  • Your healthcare provider will give Premarin Intravenous via intravenous or intramuscular injections.
  • The injection will be given slowly to prevent flushes.

What are the possible side effects of Premarin Intravenous?

Premarin Intravenous is for short-term use only. However, the risks associated with oral Premarin treatment should be taken into account.

Side effects are grouped by how serious they are and how often they happen when you are treated.

Serious, but less common side effects include:

  • Heart attack
  • Stroke
  • Blood clots
  • Dementia
  • Breast cancer
  • Cancer of the lining of the uterus (womb)
  • Cancer of the ovary
  • High blood pressure
  • High blood sugar
  • Gallbladder disease
  • Liver problems
  • Enlargement of benign tumors of the uterus ("fibroids")
  • Severe allergic reactions

Call your healthcare provider right away if you get any of the following warning signs or any other unusual symptoms that concern you:

  • New breast lumps
  • Unusual vaginal bleeding
  • Changes in vision or speech
  • Sudden new severe headaches
  • Severe pains in your chest or legs with or without shortness of breath, weakness and fatigue
  • Swollen lips, tongue and face

Less serious, but common side effects include:

  • Headache
  • Breast pain
  • Irregular vaginal bleeding or spotting
  • Stomach or abdominal cramps, bloating
  • Nausea and vomiting
  • Hair loss
  • Fluid retention
  • Vaginal yeast infection

These are not all the possible side effects of Premarin. For more information, ask your healthcare provider or pharmacist for advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What can I do to lower my chances of getting a serious side effect with Premarin Intravenous?

  • If you have high blood pressure, high cholesterol (fat in the blood), diabetes, are overweight, or if you use tobacco, you may have higher chances for getting heart disease
    Ask your healthcare provider for ways to lower your chances for getting heart disease.

General information about the safe and effective use of Premarin Intravenous

Medicines are sometimes prescribed for conditions that are not mentioned in patient information leaflets. Do not use Premarin Intravenous for conditions for which it was not prescribed. Do not give Premarin Intravenous to other people, even if they have the same symptoms you have. It may harm them. Keep Premarin Intravenous out of the reach of children.

This leaflet provides a summary of the most important information about Premarin Intravenous. If you would like more information, talk with your healthcare provider or pharmacist. You can ask for information about Premarin Intravenous that is written for health professionals. To report suspected adverse reactions, contact Pfizer at 1-800-438-1985 or FDA at 1-800-FDA-1088 or

What are the ingredients in Premarin Intravenous?

Premarin Intravenous for injection contains a mixture of conjugated estrogens, which are a mixture of sodium estrone sulfate and sodium equilin sulfate and other components including sodium sulfate conjugates: 17α-dihydroequilin, 17α-estradiol, and 17β-dihydroequilin. Premarin Intravenous for injection also contains lactose, sodium citrate, simethicone, and sodium hydroxide or hydrochloric acid in dry form. The reconstituted solution is suitable for intravenous or intramuscular injection.

Each Premarin Intravenous (conjugated estrogens, USP) for injection package provides 25 mg of conjugated estrogens, USP, in dry form for intravenous or intramuscular use.

Source: National Library of Medicine. Last updated September 30, 2018.