The Irish Medicines Board has advised women that it no longer regards Hormone Replacement Therapy (HRT) as the ideal method for treating osteoporosis.
The board said it decided conventional oestrogen-only and oestrogen plus progestogen (combined) HRT was unsuitable after consulting a Europe-wide review of these products.
HRT is used by between 10 and 20 per cent of women over 45 in Ireland, to ease menopausal symptoms such as hot flushes and mood-swings. It is also used to reduce the risk of osteoporosis.
This review noted that although HRT was beneficial in the short term when the minimum effective dose was used, the risks involved in long term use outweighed the benefits. It also found that HRT is of no benefit in healthy women without symptoms.
A recent US study found that HRT increased the risk of breast cancer by a quarter and of cardiovascular side-effects by 22 per cent.
Other research carried out in Britain over the past 18 months shows that the use of HRT can, in some cases, lead to an increased risk of breast, endometrial and possibly ovarian cancer. The Million Woman Study in the UK showed that the increase in breast cancer risk begins to decline when HRT is stopped and, by five years, returns to the same level as in women who have never taken HRT.
All patient and prescribing information currently available for these products in Ireland carry extensive warnings and information about breast cancer.
The IMB said HRT has also shown to be ineffective in the treatment of cardiovascular disease as it increases the risk of heart attacks and venous thromboembolism (VTE or blood clots), especially in the first year, and increases the risk of stroke.
The therapy has also been shown to have no beneficial effects on cognitive function or on the quality of life in women who do not have menopausal symptoms.
Women are advised to contact their GPs to discuss their situation.