Drug Interaction Report

Using temsirolimus together with tamoxifen may increase the blood levels and effects of one or both medications. Contact your doctor if your condition changes or you experience increased side effects. You may need a dose adjustment or more frequent monitoring by your doctor 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.

Talk to your doctor before using tamoxifen with soy products. There is some evidence that substances present in soy may stimulate breast tumor growth and interfere with the action of tamoxifen, although this has not been proven. Whether soy products are effective for hot flashes is also uncertain. 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.

If you are receiving therapy with temsirolimus you should avoid grapefruits and grapefruit juice. Grapefruit can raise the levels of temsirolimus in your body and lead to dangerous side effects. Do not increase or decrease the amount of grapefruit products in your diet without first talking to your doctor.