Hormone replacement therapy. Close-up of Hormone Replacement Therapy (HRT) pills in a circular dispenser. HRT pills are synthetic hormones used to treat menopausal women. They counteract the hormone deficiency that occurs at menopause. These pills contain oestrogen, and often progestogen, drugs. HRT helps to prevent osteoporosis, atherosclerosis and atrophic vaginitis (where the vagina becomes thin and dry). 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.