Hormone replacement therapy. A circular dispenser of Trisequens tablets and an Estragest patch, both containing drugs used in hormone replacement therapy (HRT). HRT uses synthetic drugs to treat hormone deficiency in menopausal women. It helps to prevent osteoporosis, atherosclerosis and atrophic vaginitis (when the vagina becomes thin and dry). Both the pills and patch contain combinations of synthetic hormones oestradiol, oestriol and norethisterone acetate. The patch is applied to the skin, or the pills are taken daily on a monthly basis to coincide with the menstrual cycle. Adverse effects include nausea, tenderness of the breasts, fluid retention and leg cramps.