This inconsistency of effect has been suggested to imply a lack of meaningful impact of HRT on breast cancer risk.There is a non-statistically significant increased rate of breast cancer for hormone replacement therapy with synthetic progesterone. The risk may be reduced with bioidentical progesterone, though the only prospective study that suggested this was underpowered due to the rarity of breast cancer in the control population. There have been no randomized controlled trials as of 2018. The relative risk of breast cancer also varies depending on the interval between menopause and HRT and route of synthetic progestin administration.The most recent follow up of the Womens Health Initiative participants demonstrated a lower incidence of breast cancer in post-hysterectomy participants taking equine estrogen alone, though the relative risk was increased if estrogen was taken with medroxy-progesterone. Estrogen is usually only given alone in the setting of a hysterectomy due to the increased risk of vaginal bleeding and uterine cancer with unopposed estrogen.HRT has been more strongly associated with risk of breast cancer in women with lower body mass indices (BMIs). No breast cancer association has been found with BMIs of over 25.
Some reported adverse events include changes in color vision, blood clots, and allergic reactions such as anaphylaxis. Whether the risk of venous thromboembolism (blood clots) is actually increased is a matter of debate. The risk is mentioned in the product literature, and they were reported in post marketing experience. Despite this, and the inhibitory effect of tranexamic acid on blood clot breakdown, large studies of the use of tranexamic acid have not shown an increase in the risk of venous or arterial thrombosis, even in people who had previously experienced thrombosis under other circumstances. Special populations
Tranexamic acid is categorized as pregnancy category B. No harm has been found in animal studies. Small amounts appear in breast milk if taken during lactation. If it is required for other reasons, breastfeeding may be continued. In kidney impairment, tranexamic acid is not well studied. However, due to the fact that it is 95% excreted unchanged in the urine, it should be dose adjusted in patients with renal impairment. In liver impairment, dose change is not needed as only a small amount of the drug is metabolized through the liver. Society and culture
Tranexamic acid was first synthesized in 1962 by Japanese researchers Shosuke and Utako Okamoto. It has been included in the WHO list of essential medicines. Brand names
Tranexamic acid is marketed in the U.S. and Australia in tablet form as Lysteda and in Australia, Sweden and Jordan it is marketed in an IV form and tablet form as Cyklokapron, in the UK and Sweden as Cyclo-F.