Oestriol Aspen

What Is Oestriol Aspen and What Is It Used For?

Oestriol Aspen is a hormone replacement therapy (HRT) medication containing estriol, a naturally occurring female estrogen. It is used to relieve menopausal urogenital symptoms, particularly vaginal dryness and irritation (vaginal atrophy), caused by the natural decline in estrogen production after menopause.

After menopause, the ovaries significantly reduce their production of estrogen. This decline affects many tissues throughout the body, but the urogenital tract is particularly sensitive. The vaginal and urethral mucous membranes become thinner, drier, and more fragile, a condition medically known as vulvovaginal atrophy or genitourinary syndrome of menopause (GSM). This can cause discomfort, itching, burning sensations, and pain during intercourse, significantly impacting quality of life.

Oestriol Aspen works by replacing the estrogen that the ovaries no longer produce in sufficient quantities. Estriol is one of three naturally occurring estrogens in the female body (alongside estradiol and estrone). It has a relatively short duration of action compared to estradiol, which is considered to give it a somewhat more favorable safety profile for certain applications, although it still carries the general risks associated with estrogen therapy.

By restoring estriol levels in the urogenital tissues, Oestriol Aspen helps maintain the elasticity, moisture, and natural resistance of the vaginal mucosa. This not only relieves the uncomfortable symptoms of vaginal atrophy but also helps protect against urogenital infections by supporting the normal acidic environment of the vagina, which serves as a natural defense mechanism against bacterial and fungal pathogens.

How does estriol differ from other estrogens?

Estriol is one of the three main estrogens produced by the human body. While estradiol is the most potent and the primary estrogen during reproductive years, estriol is the weakest of the three. During pregnancy, the placenta produces large amounts of estriol, making it the dominant estrogen of pregnancy. Its weaker estrogenic activity means it has a shorter duration of receptor binding compared to estradiol, which is why it is sometimes preferred for local urogenital therapy.

However, it is important to understand that even though estriol is a weaker estrogen, systemic oral administration (as in Oestriol Aspen tablets) still carries the general risks associated with hormone replacement therapy. The European Medicines Agency (EMA) and other regulatory bodies classify oral estriol as systemic HRT, meaning it is subject to the same prescribing considerations and risk assessments as other estrogen products used in HRT.

What Should You Know Before Taking Oestriol Aspen?

Before starting Oestriol Aspen, your doctor will assess your medical history, family history, and perform appropriate examinations. HRT carries risks that must be carefully weighed against benefits. There are several conditions where Oestriol Aspen must not be used and others that require special caution.

The decision to use hormone replacement therapy is a personal one that should be made in consultation with your doctor after a thorough assessment of your individual risk factors and the severity of your symptoms. Before starting or restarting treatment, your doctor will take a detailed medical history covering both your own health and your family history, particularly regarding hormone-sensitive cancers and blood clotting disorders.

Your doctor may perform a general physical examination and a gynecological examination, which may include breast examination. Once you begin treatment, regular follow-up appointments are essential – at least once a year – to reassess whether the benefits of continuing HRT still outweigh the risks. You should also have regular breast examinations as recommended by your doctor and participate in breast cancer screening programs (mammography) when invited.

Contraindications

Do not take Oestriol Aspen if any of the following conditions apply to you. If you are unsure whether any of these apply, speak to your doctor before taking the medication:

• You have or have had breast cancer, or there is suspicion of breast cancer
• You have or have had an estrogen-dependent cancer, such as endometrial cancer, or such cancer is suspected
• You have unexplained vaginal bleeding that has not been investigated by a doctor
• You have untreated endometrial hyperplasia (excessive thickening of the uterine lining)
• You have or have had venous thromboembolism – blood clots in the legs (deep vein thrombosis) or lungs (pulmonary embolism)
• You have a blood clotting disorder such as protein C, protein S, or antithrombin deficiency
• You have or have recently had any arterial thromboembolic disease such as heart attack, stroke, or angina pectoris
• You have or have had liver disease and your liver function tests remain abnormal
• You have porphyria, a rare inherited blood disorder
• You have a rare hereditary condition of galactose intolerance, total lactase deficiency, or glucose-galactose malabsorption
• You are allergic to estriol or any other ingredient in the medication

Warnings and Precautions

Tell your doctor if you have or have had any of the following conditions before starting treatment, as they may recur or worsen during treatment with Oestriol Aspen:

• Uterine fibroids (myomas), endometriosis, or previous endometrial hyperplasia
• Increased risk of blood clots (see section on venous thromboembolism below)
• A close relative who has had breast cancer or other estrogen-dependent cancer
• High blood pressure
• Liver disorders, such as liver adenoma (benign liver tumor)
• Gallstone disease
• Diabetes mellitus
• Migraine or severe headaches
• Systemic lupus erythematosus (SLE)
• Epilepsy
• Asthma
• Otosclerosis (a condition affecting hearing)
• Very high blood lipid levels (triglycerides)
• Fluid retention due to heart or kidney disease
• Hereditary or acquired angioedema

If you have hepatitis C and are taking antiviral combinations containing ombitasvir/paritaprevir/ritonavir (with or without dasabuvir) or glecaprevir/pibrentasvir, inform your doctor. These drug combinations used with estrogen-containing products may cause elevated liver enzyme levels (ALT). The risk with Oestriol Aspen is currently unknown, and your doctor will advise you accordingly.

Pregnancy and Breastfeeding

Oestriol Aspen is intended for women who have gone through menopause. If you become pregnant while taking Oestriol Aspen, stop the medication immediately and contact your doctor. Oestriol Aspen must not be used during pregnancy or while breastfeeding.

How Does Oestriol Aspen Interact with Other Drugs?

Several medications can reduce the effectiveness of Oestriol Aspen or be affected by it, including anti-epileptic drugs, tuberculosis treatments, HIV medications, St. John’s Wort, and certain hepatitis C antivirals. Always inform your doctor about all medications you are taking.

Drug interactions with Oestriol Aspen can occur in two ways: other medications may reduce the effectiveness of estriol by increasing its metabolic breakdown, or Oestriol Aspen may alter the way other medications work in the body. Either type of interaction can lead to reduced therapeutic efficacy or unexpected side effects, including irregular bleeding. Understanding these interactions is essential for safe and effective treatment.

Enzyme-inducing medications are the most clinically significant group of interacting drugs. These medications increase the activity of liver enzymes (particularly cytochrome P450 enzymes) that metabolize estrogens, leading to faster breakdown and reduced blood levels of estriol. This can result in diminished symptom relief and breakthrough bleeding. If you are taking any enzyme-inducing medication, your doctor may need to adjust your Oestriol Aspen dose or consider alternative treatments.

Major Interactions

Minor Interactions

What Is the Correct Dosage of Oestriol Aspen?

The initial dose of Oestriol Aspen is 2–3 mg daily for 2–3 weeks, followed by a maintenance dose of 1–2 mg daily. Your doctor will aim for the lowest effective dose for the shortest necessary duration. Take the tablets with water at the same time each day.

Your doctor will individualize your Oestriol Aspen dosage based on the severity of your symptoms, your response to treatment, and your overall health profile. The guiding principle of HRT prescribing is to use the lowest dose that provides adequate symptom relief for the shortest period of time that is clinically necessary. This approach minimizes exposure to the potential risks associated with long-term estrogen use.

Adults

Swallow the tablets whole with water or another beverage. Take your entire daily dose at approximately the same time each day to maintain consistent hormone levels. You may take the medication with or without food – there are no specific dietary restrictions.

Children

Oestriol Aspen is not indicated for use in children. This medication is intended exclusively for postmenopausal women.

Elderly

There is limited experience with HRT in women whose menopause occurred prematurely (due to ovarian failure or surgical removal of the uterus). If you belong to this group, the risks of HRT may be different, and you should discuss this with your doctor. For women over 65, there may be a slightly higher risk of memory loss associated with initiating HRT. Your doctor will help assess whether the benefits outweigh the risks for your specific situation.

Missed Dose

If you forget to take a dose, take it as soon as you remember, provided that fewer than 12 hours have passed since the scheduled time. If more than 12 hours have elapsed, skip the missed dose entirely and take your next dose at the usual time. Do not take a double dose to compensate for the one you missed. Doubling up on doses does not improve symptom control and may increase the risk of side effects.

Overdose

If you take more Oestriol Aspen than prescribed, or if a child accidentally ingests the medication, contact a doctor, hospital emergency department, or poison control center immediately for risk assessment and guidance. Symptoms of estrogen overdose may include nausea, vomiting, and vaginal bleeding. Treatment is generally supportive, as there is no specific antidote for estrogen overdose.

Before Surgery

If you are scheduled for surgery, inform the operating surgeon that you are taking Oestriol Aspen. You may need to stop taking the medication 4 to 6 weeks before the procedure to reduce the risk of blood clots. This is particularly important for major surgeries or procedures that involve prolonged immobilization. Ask your doctor when it is safe to resume taking Oestriol Aspen after surgery.

What Are the Risks of Hormone Replacement Therapy?

HRT is associated with increased risks of endometrial cancer (when estrogen is used alone in women with a uterus), breast cancer, ovarian cancer, blood clots (DVT/PE), stroke, and heart disease. The risks increase with duration of use. It is not fully established whether Oestriol Aspen carries the same level of risk as other HRT products.

Understanding the risks associated with hormone replacement therapy is essential for making an informed treatment decision. The evidence base for HRT risks comes primarily from large observational studies and randomized controlled trials, most notably the Women’s Health Initiative (WHI) and the Million Women Study. While these studies mostly examined estradiol-based HRT products, regulatory authorities generally apply their findings to all systemic estrogen therapies, including oral estriol.

Endometrial Cancer Risk

Use of estrogen-only HRT increases the risk of excessive thickening of the uterine lining (endometrial hyperplasia) and endometrial cancer in women who still have their uterus. Adding progestogen for at least 12 days per 28-day cycle provides protection against this additional risk. If your uterus has been surgically removed (hysterectomy), consult your doctor about whether you can take Oestriol Aspen without progestogen.

To put this risk in perspective: among women aged 50–65 who still have their uterus and do not take HRT, approximately 5 in 1,000 will be diagnosed with endometrial cancer. For women in the same age group taking estrogen-only HRT, between 10 and 60 per 1,000 users will be diagnosed, depending on the dose and duration of use (i.e., 5–55 extra cases).

Breast Cancer Risk

Evidence indicates that HRT with combined estrogen-progestogen, and to a lesser extent estrogen alone, increases the risk of breast cancer. The increased risk becomes apparent within 3 years of starting treatment. After stopping, the elevated risk gradually decreases over time, but may persist for 10 years or more if HRT was used for more than 5 years.

Comparative data for women aged 50 starting HRT for 5 years: among 1,000 women not taking HRT, 13–17 will be diagnosed with breast cancer during a 5-year period. For estrogen-only HRT users, 16–17 cases per 1,000 (0–3 extra cases). For combined estrogen-progestogen users, 21 cases per 1,000 (4–8 extra cases). It is not established whether Oestriol Aspen carries the same breast cancer risk as other HRT products.

Ovarian Cancer Risk

Ovarian cancer is rare, much rarer than breast cancer. HRT use (estrogen-only or combined estrogen-progestogen) has been associated with a slightly elevated risk. Among women aged 50–54 not taking HRT, approximately 2 per 2,000 will be diagnosed with ovarian cancer over a 5-year period. For women who have taken HRT for 5 years, there will be approximately 3 cases per 2,000 (about 1 extra case). It is unclear whether long-term treatment with low-dose estrogens such as Oestriol Aspen carries a lower risk than other estrogen products.

Blood Clot Risk (Venous Thromboembolism)

The risk of venous blood clots is 1.3–3 times higher for women taking HRT compared to non-users, especially during the first year of treatment. Blood clots can be serious: if one reaches the lungs (pulmonary embolism), it can cause chest pain, breathlessness, collapse, or even death. It is not established whether Oestriol Aspen increases this risk to the same extent as other HRT products.

You are more likely to develop a blood clot if: you have been unable to walk or stand for an extended period due to major surgery, injury, or illness; you are significantly overweight (BMI over 30 kg/m²); you have a blood clotting disorder; a close relative has had blood clots; you have systemic lupus erythematosus (SLE); or you have cancer.

Stroke and Heart Disease Risk

The risk of stroke is approximately 1.5 times higher for HRT users compared to non-users. For women in their 50s not taking HRT, approximately 8 in 1,000 are expected to have a stroke over a 5-year period, compared to 11 in 1,000 HRT users (3 extra cases). For women over 60 taking combined estrogen-progestogen HRT, the risk of heart disease is slightly higher than for non-users. There is no increased heart disease risk for women without a uterus taking estrogen alone.

What Are the Side Effects of Oestriol Aspen?

Common side effects of Oestriol Aspen include breast tenderness and swelling, minor vaginal bleeding, nausea, fluid retention (swollen ankles or feet), and flu-like symptoms. Most side effects are mild and typically resolve within the first few weeks of treatment. Serious side effects related to HRT include blood clots, stroke, and cancer risks.

Like all medications, Oestriol Aspen can cause side effects, although not everyone experiences them. Side effects are generally mild and transient, and they may also indicate that the dose is too high. If you experience side effects that worsen or persist, or if vaginal bleeding occurs, contact your doctor. The frequency of most side effects from Oestriol Aspen cannot be estimated from available clinical data.

For most patients, side effects such as breast tenderness, nausea, and fluid retention resolve within the first few weeks of treatment as the body adjusts to the restored estrogen levels. If vaginal bleeding occurs or any side effects become severe or persistent, contact your doctor promptly. Your doctor may adjust the dose or consider alternative treatment options.

How Should You Store Oestriol Aspen?

Store Oestriol Aspen out of the sight and reach of children. No special storage conditions are required. Do not use the medication after the expiry date printed on the packaging.

Oestriol Aspen tablets do not require any special storage conditions. Keep the medication in its original packaging to protect it from light and moisture. Store at room temperature and ensure that the tablets are kept out of the sight and reach of children at all times.

Do not use Oestriol Aspen after the expiry date stated on the packaging (after “EXP”). The expiry date refers to the last day of the stated month. Dispose of expired or unused medication responsibly – do not flush it down the toilet or throw it in household waste. Return unused medications to your pharmacist for proper disposal. These measures help protect the environment.

What Does Oestriol Aspen Contain?

Oestriol Aspen tablets contain estriol as the active substance, with inactive ingredients including amylopectin, magnesium stearate, potato starch, and lactose monohydrate (86 mg per tablet).

Active Ingredient

Each tablet contains 1 mg of estriol, the active pharmaceutical ingredient responsible for the therapeutic effect. Estriol is a naturally occurring estrogen that is chemically identical to the estriol produced by the human body.

Inactive Ingredients (Excipients)

• Amylopectin – a starch component used as a binder
• Magnesium stearate – a lubricant that aids tablet manufacturing
• Potato starch – a disintegrant that helps the tablet dissolve
• Lactose monohydrate (86 mg) – a filler and bulking agent

Tablet Appearance

Oestriol Aspen 1 mg tablets are white, round, flat, with a score line and beveled edges. The tablets are marked with the code “DG” above the score line and “7” below. They are available in packs of 90 tablets (blister packaging). The score line allows the tablet to be divided if a lower dose is needed.