Formulary
Estriol: Indications, Dosing, Side Effects and Interactions
Estriol clinical drug profile including indications, dosing, side effects, cautions and interactions.
MedNext Academy | 3 min read
Estriol: Indications, Dosing, Side Effects and Interactions
Estriol clinical drug profile including indications, dosing, side effects, cautions and interactions.
Cautions
Acute porphyrias ; diabetes (increased risk of heart disease); factors predisposing to thromboembolism; history of breast nodules-closely monitor breast status (risk of breast cancer); history of endometrial hyperplasia; history of fibrocystic disease-closely monitor breast status (risk of breast cancer); hypophyseal tumours; increased risk of gall-bladder disease; migraine (or migraine-like headaches); presence of antiphospholipid antibodies (increased risk of thrombotic events); prolonged exposure to unopposed oestrogens may increase risk of developing endometrial cancer; review treatment at least annually to assess need for continued treatment; risk factors for oestrogen-dependent tumours (e.g. breast cancer in first-degree relative); symptoms of endometriosis may be exacerbated; uterine fibroids may increase in size Cautions, further information Risk of endometrial cancer The increased risk of endometrial cancer depends on the dose and duration of oestrogen-only HRT. Risk of ovarian cancer Long-term use of combined HRT or oestrogen-only HRT is associated with a small increased risk of ovarian cancer. This excess risk disappears within a few years of stopping. Risk of venous thromboembolism Women using combined or oestrogen-only HRT are at an increased risk of deep vein thrombosis and of pulmonary embolism especially in the first year of use. In women who have predisposing factors (such as a personal or family history of deep vein thrombosis or pulmonary embolism, severe varicose veins, obesity, trauma, or prolonged bed-rest) it is prudent to review the need for HRT, as in some cases the risks of HRT may exceed the benefits. Travel involving prolonged immobility further increases the risk of deep vein thrombosis. Although the level of risk of thromboembolism associated with non-oral routes of administration of HRT has not been established, it may be lower for the transdermal route compared to the oral route; studies have found the risk associated with transdermal HRT to be no greater than the baseline population risk of thromboembolism. Risk of stroke Risk of stroke increases with age, therefore older women have a greater absolute risk of stroke. Combined HRT or oestrogen-only HRT increases the risk of stroke. Risk of coronary heart disease HRT does not prevent coronary heart disease and should not be prescribed for this purpose. There is an increased risk of coronary heart disease in women who start combined HRT more than 10 years after menopause. Although very little information is available on the risk of coronary heart disease in younger women who start HRT close to the menopause, studies suggest a lower relative risk compared with older women.
Contraindications
Active arterial thromboembolic disease (e.g. angina or myocardial infarction); history of breast cancer; history of venous thromboembolism; oestrogen-dependent cancer; recent arterial thromboembolic disease (e.g. angina or myocardial infarction); thrombophilic disorder; undiagnosed vaginal bleeding; untreated endometrial hyperplasia
Side effects
Common or very common Dysuria; genital abnormalities; skin reactions; vulvovaginal disorders Uncommon Anorectal discomfort; candida infection; headache; pelvic pain Frequency not known Breast abnormalities; cervical mucus increased; dementia; erythema nodosum; gallbladder disorder; increased risk of coronary artery disease; increased risk of ischaemic stroke; increased risk of venous thromboembolism; nausea; neoplasms; vaginal haemorrhage; vomiting
Interactions
**Other interactions (5):**
- The metabolism of oestrogens may be increased by concomitant use of substances known to induce drug-metabolizing enzymes, specifically cytochrome P450 enzymes, such as anticonvulsants (e.g.
- Ritonavir and nelfinavir, although known as strong inhibitors, by contrast exhibit inducing properties when used concomitantly with steroid hormones.
- Herbal preparations containing St John's wort (Hypericum Perforatum) may induce the metabolism of oestrogens.
- Estriol may possibly increase the pharmacological effects of corticosteroids, succinylcholine, theophyllines and troleandomycin.
- Women using oestrogens other than ethinyl estradiol, such as estradiol, estriol and conjugated oestrogens had a rate of ALT elevation similar to those not receiving any oestrogens; however, due to...
Pregnancy
Not known to be harmful.
Breast feeding
Avoid; adverse effects on lactation.
Hepatic impairment
Manufacturer advises caution; avoid in acute or active disease.
Renal impairment
Use with caution. M
Medicinal forms
Pessary,Cream,Gel
Clinical governance
**Author:** MedNext Clinical Team. **Clinical reviewer:** Dr Shameer Deen, MBBS, MS, MRCS. **Sources:** BNF, Indian Pharmacopoeia, CIMS India. **Correction:** Report errors at support@mednext.academy.
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