Drug Interaction Report

Before using ethinyl estradiol, tell your doctor if you also use thyroid desiccated. You may need dose adjustments or extra monitoring to safely take both medications together. If you are already using ethinyl estradiol and thyroid desiccated, your thyroid levels may need to be measured if your dose of ethinyl estradiol is changed or stopped. You should notify your doctor if you have symptoms of low thyroid hormone levels such as tiredness, feeling cold, constipation, unexplained weight gain, depression, joint or muscle pain, thinning hair or hair loss, dry skin, hoarseness, and abnormal menstrual periods. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

The timing of meals relative to your oral thyroid desiccated dose can affect the absorption of the medication. Therefore, thyroid desiccated should be taken on a consistent schedule with regard to time of day and relation to meals to avoid large fluctuations in blood levels, which may alter its effects. In addition, absorption of thyroid desiccated may be decreased and/or delayed by foods such as soybean flour, cotton seed meal, walnuts, dietary fiber, calcium, calcium fortified juices and grapefruit or grapefruit juice. These foods should be avoided within several hours of dosing if possible. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Grapefruit juice may increase the blood levels of certain medications such as drospirenone. You may want to limit your consumption of grapefruit and grapefruit juice during treatment with drospirenone. However, if you have been regularly consuming grapefruit or grapefruit juice with the medication, then it is advisable for you to talk with your doctor before changing the amounts of these products in your diet, as this may alter the effects of your medication. Contact your doctor if your condition changes or you experience increased side effects. Orange juice is not expected to interact.

Using multivitamin with minerals together with thyroid desiccated may decrease the effects of thyroid desiccated. You should separate the administration of thyroid desiccated and multivitamin with minerals by at least 4 hours. If your doctor does prescribe these medications together, you may need a dose adjustment or special test to safely use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Consumer information for this interaction is not currently available.

MONITOR: Coadministration of ethinyl estradiol may increase the plasma concentrations of drugs that are primarily metabolized by CYP450 1A2. In a study of 30 healthy volunteers administered the CYP450 1A2 substrate tizanidine, the systemic exposure (AUC) of tizanidine was 3.9 times greater in women using an oral contraceptive containing ethinyl estradiol.

MANAGEMENT: Patients should be monitored for increased adverse effects of the CYP450 1A2 substrate during concomitant use with ethinyl estradiol. Product labeling for the specific CYP450 1A2 substrate should be consulted for additional recommendations.

Information for this minor interaction is available on the professional version.

Information for this minor interaction is available on the professional version.