Your healthcare provider should make sure you are appropriately treated for any risk factors for heart disease, strokes, or blood clots before you take Premphase. Risk factors include:
Premphase (like all estrogen/progestin medications) may increase the risk of breast cancer. Proper screening and monitoring as determined by your healthcare provider, such as yearly mammograms and monthly self breast exams, is recommended.
Let your healthcare provider know if you have abnormal vaginal bleeding, such as heavy bleeding or bleeding between periods, while taking Premphase, as this may be a sign of precancerous or cancerous changes in the uterus. Your healthcare provider can perform the necessary tests to rule out cancer.
Estrogen-containing drugs seem to increase the risk of dementia. In no case should Premphase be used to prevent or treat dementia (it is not effective for this use).
Let your healthcare provider know right away if you notice any vision changes. This can signal a blood clot in the retina, a possible side effect of Premphase.
Premphase should be used with caution in people who have low calcium levels in the blood (known medically as hypocalcemia).
Women who take estrogen-containing medications like Premphase have an increased risk for gallbladder disease.
If you have had jaundice (yellowing of the whites of the eyes or skin) due to estrogens or pregnancy in the past, Premphase could cause similar problems to recur. If this happens, your healthcare provider will probably advise you to stop taking the drug.
When possible, Premphase should be stopped four to six weeks before many surgeries in order to help prevent blood clots.
If you have an underactive thyroid (hypothyroidism), Premphase may increase your body's requirement for thyroid hormones. Your healthcare provider should monitor you and adjust the dose of your thyroid medications as necessary.
Premphase can cause fluid retention. This can cause problems for people with congestive heart failure (CHF) or kidney problems.
It is not clear if Premphase increases the risk of ovarian cancer. Some studies have shown an increased risk, while others have not.
The medication does pass through breast milk. Therefore, if you are breastfeeding or plan to start, discuss this with your healthcare provider prior to taking Premphase (see Premphase and Breastfeeding).