Estradiol is a form of estrogen, a female sex hormone that regulates many processes in the body.

Norgestimate is a form of progesterone, a female hormone important for regulating ovulation and menstruation.

Prefest is a combination medicine used to treat menopause symptoms such as hot flashes and vaginal changes, and to prevent osteoporosis (bone loss) in menopausal women.

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

You should not use Prefest if you have had a hysterectomy, or if you have: undiagnosed vaginal bleeding, liver disease, a bleeding disorder, if you will have major surgery, or if you have ever had a heart attack, a stroke, a blood clot, or cancer of the breast, uterus/cervix, or vagina.

Do not use if you are pregnant.

Prefest may increase your risk of developing a condition that may lead to uterine cancer. Report any unusual vaginal bleeding right away.

Using this medicine can increase your risk of blood clots, stroke, heart attack, or cancer of the breast, uterus, or ovaries. Prefest should not be used to prevent heart disease, stroke, or dementia.

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Prefest usually comes in a pack of pills that are different colors. In most cases you will take a pill of one color for 3 days in a row, and then take a pill of the other color for the next 3 days in a row. This cycle is then repeated throughout your treatment.

Each time you start a new pack, start with the first tablet in the first row of pills. Your medicine may come with stickers to mark your weekday schedule on the pack.

Be sure to have a new pack of Prefest ready to start on the day after you have finished an entire pill pack.

Estradiol may increase your risk of developing a condition that may lead to uterine cancer. Call your doctor at once if you have any unusual vaginal bleeding while using this medicine.

If you need major surgery or will be on long-term bed rest, you may need to stop using this medicine for a short time. Any doctor or surgeon who treats you should know that you are using Prefest.

Your doctor should check your progress on a regular basis (every 3 to 6 months) to determine whether you should continue this treatment. Self-examine your breasts for lumps on a monthly basis and have a mammogram every year while using Prefest.

Store at room temperature away from moisture, heat, and light.

You should not use this medicine if you are allergic to estradiol or norgestimate, if you have had a hysterectomy, or if you have:

• unusual vaginal bleeding that has not been checked by a doctor;

• liver disease;

• a history of heart attack, stroke, or blood clot; or

• a history of hormone-related cancer, or cancer of the breast, uterus/cervix, or vagina.

Do not use Prefest if you are pregnant. Tell your doctor right away if you become pregnant during treatment.

Using this medicine can increase your risk of blood clots, stroke, or heart attack. You are even more at risk if you have high blood pressure, diabetes, high cholesterol, if you are overweight, or if you smoke.

Prefest should not be used to prevent heart disease, stroke, or dementia, because this medicine may actually increase your risk of developing these conditions.

Tell your doctor if you have ever had:

• heart disease;

• liver problems, or jaundice caused by pregnancy or taking hormones;

• kidney disease;

• gallbladder disease;

• asthma;

• epilepsy or other seizure disorder;

• migraines;

• lupus;

• porphyria (a genetic enzyme disorder that causes symptoms affecting the skin or nervous system);

• endometriosis or uterine fibroid tumors;

• a thyroid disorder; or

• high levels of calcium in your blood.

Using estradiol may increase your risk of cancer of the breast, uterus, or ovaries. Talk with your doctor about this risk.

Prefest can slow breast milk production. Tell your doctor if you are breast-feeding.

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

If you miss 2 doses in a row, take the next tablet in order and keep taking only one pill per day. Call your doctor if you miss more than 2 doses of this medicine.

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

Avoid smoking. It can greatly increase your risk of blood clots, stroke, or heart attack while using Prefest.

Grapefruit may interact with Prefest and lead to unwanted side effects. Avoid the use of grapefruit products.

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

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

• heart attack symptoms--chest pain or pressure, pain spreading to your jaw or shoulder, nausea, sweating;

• signs of a stroke--sudden numbness or weakness (especially on one side of the body), sudden severe headache, slurred speech, problems with vision or balance;

• signs of a blood clot--sudden vision loss, stabbing chest pain, feeling short of breath, coughing up blood, pain or warmth in one or both legs;

• swelling or tenderness in your stomach;

• jaundice (yellowing of the skin or eyes);

• memory problems, confusion, unusual behavior;

• unusual vaginal bleeding, pelvic pain;

• a lump in your breast; or

• high levels of calcium in your blood--nausea, vomiting, constipation, increased thirst or urination, muscle weakness, bone pain, lack of energy.

Common side effects of Prefest may include:

• nausea, vomiting, bloating, stomach cramps;

• fluid retention (swelling, rapid weight gain);

• headache;

• breast pain;

• thinning scalp hair; or

• vaginal itching or discharge, changes in your menstrual periods, breakthrough bleeding.

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.

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Many drugs can affect Prefest. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any medicine you start or stop using.