Introduction

Tamoxifen citrate (C32H37NO8) is an organic compound. Tamoxifen citrate is a selective estrogen receptor modulator (SERM) that is widely used in the treatment of breast cancer. It works by blocking the estrogen receptor in breast tissue, which inhibits the growth of estrogen-dependent cancer cells. Tamoxifen is also used in the prevention of breast cancer in high-risk individuals.

Tamoxifen citrate is commonly prescribed for both the treatment and prevention of breast cancer. It is effective in reducing the recurrence of breast cancer and improving survival rates in patients with estrogen receptor-positive (ER-positive) breast cancer. In addition to its use in cancer therapy, Tamoxifen has been studied for its potential applications in conditions like osteoporosis and infertility.

To maintain its stability, tamoxifen citrate should be stored in a cool, dry place away from direct sunlight. Patients should follow prescribed dosages and consult with a healthcare provider before use, as Tamoxifen may cause side effects such as hot flashes, nausea, or an increased risk of blood clots. Regular monitoring and check-ups are essential during treatment with Tamoxifen.

Figure 1 Characteristics of Tamoxifen citrate

How to use Tamoxifen citrate

Tamoxifen citrate is used as an antiestrogen with potent anti-cancer and PKC inhibitory activities. Tamoxifen citrate functions as an estrogen receptor antagonist in breast tissue. Tamoxifen Citrate is an agonist towards this receptor in tissues of the endometrium. Tamoxifen Citrate inhibits DNA synthesis and transcription by recruiting co-repressors, which stop estrogen from interacting with genes. When combined with PAX2, Tamoxifen Citrate can inhibit the proliferation of ERBB2. It is also a high-affinity activator of the GPR30 receptor. Tamoxifen Citrate is an activator of Estrogen Receptor.

Pharmacological effects of Tamoxifen citrate

Tamoxifen citrate is a nonsteroidal antiestrogenic drug. Can bind to estrogen receptors in breast cells, drug-receptor complexes are not easily dissociated, do not stimulate transcription, or have weak effects. Tamoxifen can upregulate transforming growth factor beta, which is associated with the development of malignant tumors. It also has a specific inhibitory effect on protein kinase C. These effects have inhibitory effects on tumor cells that rely on estrogen to continue growing.

The side effects of Tamoxifen citrate

The most common side effects caused by Tamoxifen citrate are nausea, hot flashes, vaginal dryness, and loss of sexual desire. Notably, Tamoxifen citrate is not an antagonist in all tissues like in breast tissue. It therefore has an agonist effect on bones and ovaries. In addition, it does not have a cardioprotective effect on the heart and causes thromboembolism and fatty liver. It shows a reduction in libido and evidence of decreased cognition has been reported. The side effect of Tamoxifen citrate at the mitochondrial level lies in an increased reactive oxygen species pathway due to Tamoxifen citrate within the mitochondria of a cell leading to apoptosis[13]. It may also prove that Tamoxifen citrate may lead to an aging process as it has been used by breast cancer patients for more than 5 years. Less common side effects include anxiety, blistering, peeling, or loosening of the skin and mucous membranes, blurred vision, cataracts in the eyes or other eye problems, change in vaginal discharge, chest pain, chills, confusion, cough, dizziness, fainting, fast heartbeat, fever, hoarseness, lightheadedness, lower back or side pain, pain or feeling of pressure in the pelvis, pain or swelling in the legs, pain, redness, or swelling in your arm or leg, painful or difficult urination, rapid shallow breathing, shortness of breath or trouble with breathing, skin rash or itching over the entire body, sweating, weakness or sleepiness, wheezing, vaginal bleeding and yellow eyes or skin. More common side effects are absent, missed, or irregular periods and a decrease in the amount of urine. There seems to be a correlation between long-term Tamoxifen citrate administration and endometrial proliferation[14]. Mild-moderate gastrointestinal toxicity (diarrhea, anorexia) and reversible neurotoxicity were observed in dogs receiving chemotherapy plus high-dose Tamoxifen citrate given for seven days[15]. Nausea and vomiting can occur. Dizziness, lethargy, depression, irritability, and cerebellar dysfunction have been described.