Tamoxifen: learn about side effects, dosage, special precautions, and more on MedlinePlus Find patient medical information for Tamoxifen Oral on WebMD including its uses, side effects and safety, interactions, pictures, warnings and user ratings. Find a comprehensive guide to possible side effects including common and rare side effects when taking Nolvadex (Tamoxifen Citrate) for healthcare professionals and. Learn about the potential side effects of Nolvadex (tamoxifen). Includes common and rare side effects information for consumers and healthcare professionals. Find a comprehensive guide to possible side effects including common and rare side effects when taking Aromasin (Exemestane) for healthcare professionals and consumers. Tamoxifen is the oldest of the hormonal therapies, drugs that block the effects of estrogen in the breast tissue. Tamoxifen is approved by the FDA to treat people. Tamoxifen, sold under the brand name Nolvadex among others, is a medication that is used to prevent breast cancer in women and treat breast cancer in women and men. Tamoxifen blocks the actions of estrogen and is used to treat and prevent some types of breast cancer. Learn about side effects, interactions and indications. Tamoxifen is an Estrogen AgonistAntagonist. The mechanism of action of tamoxifen is as a Selective Estrogen Receptor Modulator. Tamoxifen is a drug taken orally in pill form. For over a quarter of a century, physic Tamoxifen (Nolvadex), a hormone therapy drug, is used to treat breast cancers and to lower risk in women at high risk of breast cancer. Read about Tamoxifen side.