Progesterone (Prometrium) is an oral medication used to protect the uterus in postmenopausal women (those who've gone through menopause) who are also taking estrogen. It can also help regulate menstrual cycles in people who aren't getting their period. The medication is typically taken by mouth once at bedtime for 10-12 days, depending on what you're taking it for. Potential side effects include headache, weight gain or weight loss, and breast tenderness.
Protection of the uterus for postmenopausal women also taking estrogen medications
Lack of menstrual periods due to hormone imbalance
Progesterone (Prometrium) is a progestin. It works by protecting the uterus from becoming too thick. It also helps regulate periods by giving the body more progesterone, a hormone that helps control the menstrual cycle. This helps to balance the natural levels of progesterone in the body.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Less common
Clear or bloody discharge from the nipple
dimpling of the breast skin
inverted nipple
lump in the breast or under the arm
persistent crusting or scaling of the nipple
redness or swelling of the breast
sore on the skin of the breast that does not heal
Incidence not known
Abdominal or stomach pain
blurred vision
change in vaginal discharge
clay-colored stools
cleft lip or palate
confusion
darkened urine
difficult or labored breathing
difficulty with swallowing
difficulty with walking
dizziness
dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
fainting
fast, pounding, or irregular heartbeat or pulse
headache
indigestion
irregular heartbeat
irritation
joint pain, stiffness, or swelling
lightheadedness
loss of appetite
nervousness
noisy breathing
numbness or tingling in the face, arms, or legs
pain or feeling of pressure in the pelvis
pains in the stomach, side, or abdomen, possibly radiating to the back
pounding in the ears
puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
rash
redness of the skin
shortness of breath
slow heartbeat
spontaneous abortion
stomach or pelvic discomfort, aching, or heaviness
sweating
swelling of the eyelids, face, lips, hands, or feet
tightness in the chest
trouble speaking, thinking, or walking
unpleasant breath odor
unusual tiredness or weakness
vaginal bleeding
vomiting
vomiting of blood
yellow eyes or skin
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. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Incidence not known
Attack, assault, or force
blurred or loss of vision
change in walking and balance
changes in behavior
changes in patterns and rhythms of speech
choking
clumsiness or unsteadiness
confusion about identity, place, and time
continuing ringing or buzzing or other unexplained noise in the ears
decreased awareness or responsiveness
difficulty with moving
disturbed color perception
double vision
drowsiness
extreme dizziness or drowsiness
feeling drunk
feeling of constant movement of self or surroundings
feeling of unreality
hair loss or thinning of the hair
halos around lights
hearing loss
hives or welts
longer or heavier menstrual periods
loss of consciousness
muscle cramps
muscle stiffness
night blindness
normal menstrual bleeding occurring earlier, possibly lasting longer than expected
overbright appearance of lights
redness of the skin
relaxed and calm
sensation of spinning
sense of detachment from self or body
severe sleepiness
sleepiness
slurred speech
swollen tongue
thoughts of killing oneself
tunnel vision
weight changes
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.
Helps protect the uterus and regulate periods
Taken by mouth once a day
Might be easier to take than the injection form
Not a good option for people with liver problems
Shouldn't be used in people with a peanut allergy
Potentially raises your risk of serious blood clots
Take progesterone (Prometrium) at bedtime since it can make you feel tired or dizzy. Don't drive or perform dangerous activities without seeing how it affects you.
If you're having trouble swallowing progesterone (Prometrium) capsules, stand upright and take them with a glass of water to help get the capsule down to your stomach faster.
Progesterone (Prometrium) contains peanut oil, so tell your prescriber if you're allergic to peanuts. Speak with your care team about all of your allergies so they can make sure this medication is safe for you.
If you're taking progesterone (Prometrium) to regulate your period, your period should start within 7 days after the last capsule. If your period doesn't start by this point, let your prescriber know. If you've been sexually active, you should also take a pregnancy test.
Let your prescriber know if you experience unusual or heavy vaginal bleeding, lumps in your breast, changes to your vision, or severe headaches after starting progesterone (Prometrium). These are not typical side effects and could be a sign of more serious problems.
Since progesterone (Prometrium) raises your risk for serious blood clots and certain cancers, speak regularly with your prescriber about if you should continue taking this medication.
Progesterone (Prometrium) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Taking progesterone (Prometrium) with estrogens | Personal or family history of blood clots | High blood pressure | Diabetes | High cholesterol | Smoking | Obesity | Systemic lupus erythematosus (SLE)
Progesterone (Prometrium) can raise your risk of blood clots, especially when taken with estrogen medications. This can be very dangerous and lead to heart attack, stroke, or pulmonary embolism (life-threatening blood clot in the lungs). Be sure to discuss all your medical conditions with your prescriber before starting progesterone (Prometrium). Call 911 or seek immediate medical attention if you have pain in your legs or arms, chest pain, sudden severe headaches, trouble breathing, or sudden changes in your speech.
Risk factors: Personal or family history of breast cancer | Long-term use of estrogen and progesterone (Prometrium) together
There's a higher risk of developing breast cancer when taking progesterone (Prometrium) and estrogen medications together. The longer you take this combination, the higher your risk is. That's why it's best to use progesterone (Prometrium) only for the shortest amount of time needed. Follow up with your prescriber regularly so they can make sure you still need to take this medication.
Risk factors: Age 65 or older | Taking progesterone (Prometrium) with estrogens
People taking progesterone (Prometrium) and estrogen medications together might have a higher risk of developing dementia. While experts aren't sure why this happens, your risk is highest if you start using this combination for the first time at the age of 65 or older. If you or your loved one notices that you're becoming forgetful, confused, anxious, or are having a hard time making decisions or solving problems, let your prescriber know.
Progesterone (Prometrium) can cause retinal thrombosis, or a blood clot in the eyes. Speak to your prescriber right away if you notice changes in your vision, sudden vision loss, bulging eyes, double vision, or migraine.
Progesterone (Prometrium) capsules can cause you to feel dizzy or sleepy. This is temporary but can affect your concentration and focus. It's best to take progesterone (Prometrium) right before you go to bed, so that you're less likely to feel this way during the day. Don't drive or perform dangerous activities until you feel better.
Risk factors: Heart failure | Kidney problems
Progesterone (Prometrium) can cause extra fluid to build up in your body, especially in your legs, ankles, and feet. This is more likely to happen if you have certain conditions like kidney problems or heart failure. The extra fluid can cause these other conditions to get worse. If you know you have problems with fluid buildup or swelling, tell your prescriber before you start using progesterone (Prometrium). Call your prescriber or seek medical help right away if you notice unexplainable swelling, unexplained weight gain, or sudden trouble breathing.
Uterus protection: The typical dose is 200 mg by mouth once a day at bedtime for 12 days in a row. Repeat these directions every 28 days.
Lack of menstrual periods: The typical dose is 400 mg by mouth once a day at bedtime for 10 days. You should expect a period within 7 days of your last capsule.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Allergy to peanuts
Undiagnosed abnormal vaginal bleeding
Breast cancer
Blood clotting problems
Liver problems
Currently pregnant
Protection of the uterus for postmenopausal women also taking estrogen medications
Lack of menstrual periods due to hormone imbalance
Lack of menstrual periods due to hormone imbalance
Irregular periods due to hormone imbalance
Protection of the uterus in postmenopausal women who are taking estrogen medications
Lack of menstrual periods due to hormone imbalance
Abnormal bleeding from the uterus due to hormone imbalance
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Acertis Pharmaceuticals, LLC. (2024). Prometrium- progesterone capsule [package insert]. DailyMed.
American College of Obstetricians and Gynecologists. (2024). Endometrial hyperplasia.
Fitzpatrick, L. A., et al. (1999). Micronized progesterone: Clinical indications and comparison with current treatments. Fertility and Sterility.
Lord, M., et al. (2024). Secondary amenorrhea. StatPearls.
MedlinePlus. (2024). Retinal vein occlusion.
Society for Assisted Reproductive Technology. (n.d.). Progesterone.
You and Your Hormones. (2021). Progesterone.
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