Patient/caregiver was instructed upon therapeutic uses and mechanism of action of Megestrol as follows:
- Megestrol is a synthetic progesterone sex hormone. Megestrol can be used as an antineoplastic medication, which brings about hormonal changes contributing to inhibitory effects on the growth of tumor masses in the breast and uterine tissues.
- Excessive exposure to estrogen in women is considered to be an important factor stimulating the growth of established tumors along with development of new tumors in the breast tissue and endometrium of uterus.
- Estrogen in women acts on the estrogen receptors in the breast and endometrial tissues and contribute to the growth of tumors.
- Megestrol increases the metabolism of estrogen in the body and thus, reduces the plasma concentrations of the hormone.
- Reduced estrogen availability in the body leads to reduced exposure of estrogen receptors in the breast and endometrial tissues to estrogen, which inhibits growth of tumors in these tissues.
- Megestrol is also known to help with weight gain, by inhibiting cachexin, which is a hormone contributing to weight loss and wasting in cancer and AIDS patients. Megestrol use in these individuals also has side-effects of increasing the general body metabolism and stimulation of appetite. These side-effects of megestrol use can help with improving appetite and promoting weight gain in cancer and AIDS patients.
