Blissel (Estriol) Vaginal Gel
Local vaginal estrogen for the treatment of vaginal atrophy and menopausal dryness
Quick facts about Blissel
Key takeaways about Blissel
- Low systemic absorption: Blissel acts locally in the vagina with minimal hormone entering the bloodstream, making it safer than oral HRT for treating vaginal symptoms
- No progestogen needed: Unlike systemic estrogen therapy, Blissel does not require additional progestogen to protect the uterine lining
- Simple dosing schedule: Daily application for 3 weeks, then reduced to twice weekly for maintenance
- Contraindicated in breast cancer: Do not use if you have or have had breast cancer, estrogen-sensitive cancers, or unexplained vaginal bleeding
- Regular check-ups essential: Visit your healthcare provider at least once a year while using Blissel to reassess whether continued treatment is appropriate
What Is Blissel and What Is It Used For?
Blissel is a vaginal gel containing estriol, a naturally occurring estrogen hormone. It is used to treat vaginal atrophy — the thinning, drying, and inflammation of the vaginal walls that occurs due to declining estrogen levels after menopause. Blissel works locally in the vagina to restore the natural vaginal environment.
Blissel belongs to a group of medicines called local (vaginal) hormone replacement therapy (HRT). After menopause — defined as the permanent cessation of menstruation, typically occurring around age 51 — the ovaries gradually stop producing estrogen. This hormone decline leads to significant changes in the vaginal and urogenital tissues, a condition known medically as genitourinary syndrome of menopause (GSM), previously referred to as vulvovaginal atrophy.
GSM affects up to 50–70% of postmenopausal women and can have a significant impact on quality of life. Unlike vasomotor symptoms (hot flashes) which often improve over time, vaginal atrophy tends to be progressive and rarely resolves without treatment. Symptoms include vaginal dryness, burning, itching, discomfort during intercourse (dyspareunia), and increased susceptibility to urinary tract infections.
Blissel works by replacing the estrogen that the ovaries no longer produce in sufficient quantities. When applied vaginally, estriol acts directly on the vaginal epithelium — the thin layer of tissue lining the vagina — promoting cellular maturation and restoring its natural thickness and moisture. This local action means the hormone is delivered exactly where it is needed, with very little being absorbed into the general circulation.
The estriol in Blissel is a short-acting, weak estrogen, which is one of the three naturally occurring estrogens in the human body (along with estradiol and estrone). Because of its weak estrogenic activity and rapid metabolism, estriol has a favorable safety profile compared to more potent estrogens. Clinical studies have shown that vaginal estriol effectively restores the vaginal epithelium, normalizes vaginal pH, improves vaginal flora, and significantly reduces symptoms of vaginal atrophy.
Blissel is approved in numerous European countries under various brand names including Blissel, Estrokad, and Gelisse. The formulation and active ingredient are the same regardless of brand name. Your healthcare provider will determine whether Blissel is the appropriate treatment for your symptoms.
What Should You Know Before Using Blissel?
Before starting Blissel, your healthcare provider will review your medical history and may perform a physical examination. Blissel is contraindicated in women with breast cancer, estrogen-sensitive cancers, unexplained vaginal bleeding, or a history of venous thromboembolism. Regular follow-up appointments are essential during treatment.
Although Blissel has very low systemic absorption, it is still an estrogen-containing product and requires careful medical evaluation before use. Your healthcare provider will assess your individual risk-benefit profile, taking into account your personal and family medical history, before prescribing this treatment.
Before starting or resuming treatment with Blissel, your healthcare provider will ask about your own and your family’s medical history. A physical examination may be recommended, which could include a breast examination and/or a gynecological examination if clinically indicated. Once treatment has begun, you should attend regular check-ups at least once a year to discuss whether the benefits of continuing treatment outweigh the risks.
Contraindications
Do not use Blissel if any of the following apply to you:
- You have or have had breast cancer, or breast cancer is suspected
- You have a cancer that is sensitive to estrogen, such as endometrial cancer (cancer of the uterine lining), or this is suspected
- You have unexplained vaginal bleeding
- You have untreated endometrial hyperplasia (excessive thickening of the uterine lining)
- You have or have had a blood clot in a vein (venous thromboembolism), such as deep vein thrombosis or pulmonary embolism
- You have a known blood clotting disorder (e.g., protein C, protein S, or antithrombin deficiency)
- You have or recently had a disease caused by blood clots in the arteries, such as heart attack, stroke, or angina pectoris
- You have or have had liver disease and your liver function tests have not returned to normal
- You have a rare inherited blood disorder called porphyria
- You are allergic to estriol or any of the other ingredients in Blissel
- You develop jaundice (yellowing of the skin and eyes) or deterioration in liver function
- You experience a sudden increase in blood pressure
- You develop a new onset of migraine or unusually severe headache
- You become pregnant
- You notice signs of a blood clot: painful swelling and redness of the legs, sudden chest pain, or difficulty breathing
- Any of the conditions listed under contraindications develops for the first time
Warnings and Precautions
Tell your healthcare provider if you have or have had any of the following conditions, as they may recur or worsen during treatment with Blissel, even though this is less likely with a low-dose vaginal estrogen compared to systemic HRT:
- Very high blood lipid levels (triglycerides)
- Endometriosis or a history of endometrial hyperplasia
- Uterine fibroids (myomas)
- High blood pressure (hypertension)
- Diabetes mellitus
- Gallstones
- Migraine or severe headaches
- Systemic lupus erythematosus (SLE)
- Epilepsy
- Asthma
- Otosclerosis (a condition affecting the ear and hearing)
- Fluid retention due to heart or kidney problems
- Increased risk of blood clot formation
- Increased risk of estrogen-sensitive cancer (e.g., a first-degree relative with breast cancer)
- Liver disease, including benign liver tumors
- Hereditary or acquired angioedema (rapid swelling under the skin)
It is important to note that the applicator used with Blissel is inserted into the vagina, which may cause discomfort and tenderness in women with severe vaginal atrophy (very thin or inflamed vaginal walls). This usually improves as the treatment takes effect and the vaginal tissue begins to restore itself.
If it has been less than 12 months since your last menstrual period, or if you are under 50 years of age, you may still need to use contraception to prevent pregnancy. Consult your healthcare provider for advice.
HRT and Cancer Risk
The following cancer risks are primarily associated with systemic HRT (tablets and patches) that circulate in the bloodstream. Blissel is used locally in the vagina with very low systemic absorption, making these risks considerably lower. However, it is important to be informed:
Endometrial cancer: Long-term use of systemic estrogen-only HRT can increase the risk of endometrial cancer. It remains unclear whether this risk applies to Blissel when used repeatedly or for extended periods beyond one year. However, because Blissel has very low systemic absorption, the addition of a progestogen is not considered necessary. If you experience any unexpected vaginal bleeding, consult your healthcare provider promptly as this could indicate endometrial thickening.
Breast cancer: Current evidence suggests that Blissel does not increase the risk of breast cancer in women without a prior history of the disease. The safety of Blissel in women with a history of breast cancer has not been established. Perform regular breast self-examinations and report any changes — such as dimpling, nipple changes, or lumps — to your healthcare provider. Continue with mammography screening as recommended.
Ovarian cancer: Ovarian cancer is rare. Systemic estrogen-only HRT has been associated with a slightly increased risk. Among women aged 50–54 not taking HRT, approximately 2 in 2,000 will be diagnosed with ovarian cancer over a 5-year period. For those who have used systemic HRT for 5 years, approximately 3 in 2,000 cases are expected (roughly 1 additional case). The risk with low-dose vaginal estrogen like Blissel is expected to be negligible.
Blood Clot and Cardiovascular Risk
The following cardiovascular risks are primarily associated with systemic HRT. The risk with Blissel is expected to be very low due to its minimal systemic absorption:
Venous thromboembolism (blood clots): The risk of blood clots in veins is approximately 1.3–3 times higher for women taking systemic HRT, particularly during the first year of use. Blood clots can be serious — if one travels to the lungs, it can cause chest pain, breathlessness, collapse, or even death. Risk factors include advanced age, major surgery or prolonged immobilization, obesity (BMI over 30), clotting disorders, family history of blood clots, SLE, and cancer.
Heart disease: Systemic estrogen-only HRT has not been shown to increase the risk of heart attack.
Stroke: The risk of stroke is approximately 1.5 times higher with systemic HRT. Among women in their 50s not taking HRT, about 8 in 1,000 will have a stroke over 5 years; among those taking systemic HRT, about 11 in 1,000 are expected (3 additional cases). Again, the risk with Blissel is expected to be very low.
Pregnancy and Breastfeeding
Blissel must not be used during pregnancy. If you become pregnant while using Blissel, stop treatment immediately and contact your healthcare provider. Blissel must not be used while breastfeeding. If you are pregnant, breastfeeding, think you may be pregnant, or are planning to become pregnant, seek advice from your healthcare provider before using this medicine.
Driving and Operating Machinery
Blissel has no known effect on the ability to drive or use machines.
How Does Blissel Interact with Other Drugs?
Blissel contains a very low dose of estriol and is applied locally in the vagina. Therefore, it is not expected to significantly interact with or be affected by other medicines taken at the same time. However, Blissel may affect the efficacy of other vaginally administered treatments.
Because of its very low systemic absorption, Blissel is unlikely to interact with other medications in a clinically meaningful way. This is a notable advantage over oral or transdermal estrogen products, which circulate in the bloodstream and can interact with a wider range of medicines. However, some general considerations apply to all estrogen-containing products:
| Interacting Drug / Class | Type | Clinical Significance |
|---|---|---|
| Other vaginal preparations | Local interaction | Blissel may affect absorption or efficacy of other vaginally applied medicines. Separate administration times if possible. |
| Systemic HRT (estradiol, conjugated estrogens) | Additive effect | Concurrent use with systemic HRT should be under medical supervision to avoid excessive estrogen exposure. |
| Aromatase inhibitors (e.g., letrozole, anastrozole) | Pharmacological antagonism | Aromatase inhibitors reduce estrogen production. Vaginal estrogen could counteract their effect. Use only under specialist guidance. |
| Tamoxifen, other SERMs | Potential antagonism | Vaginal estrogen may counteract the anti-estrogen effects. Discuss with your oncologist before use. |
| Latex condoms and diaphragms | Physical interaction | Oil-based vaginal products can weaken latex. Check product compatibility. Blissel is water-based but consult your pharmacist. |
Always inform your healthcare provider and pharmacist about all medicines you are taking, including over-the-counter medicines and herbal products. While Blissel’s interaction potential is low due to its minimal systemic absorption, comprehensive medication review is always good practice.
What Is the Correct Dosage of Blissel?
The standard dosage of Blissel is one applicator dose (1 g gel containing 50 micrograms estriol) daily for the first 3 weeks, then reduced to one dose twice weekly for maintenance. Apply at bedtime using the provided applicator. Your healthcare provider will prescribe the lowest effective dose for the shortest duration necessary.
Always use Blissel exactly as described in the patient information leaflet or as directed by your healthcare provider or pharmacist. The goal is to achieve symptom relief using the lowest dose for the shortest duration needed. If you do not experience symptom relief, or if you feel the dose is too high, speak with your healthcare provider.
Adults (Postmenopausal Women)
Initial Phase (Weeks 1–3)
Dose: One applicator dose (1 g gel = 50 micrograms estriol) daily
Timing: Preferably at bedtime
Duration: 3 weeks
Note: Symptoms should begin to improve during this phase
Maintenance Phase (Week 4 onwards)
Dose: One applicator dose twice weekly
Timing: Preferably at bedtime, on the same days each week
Duration: As directed by your healthcare provider — reviewed at least annually
Note: Continue only as long as symptoms require treatment
Children and Adolescents
Blissel is not indicated for use in children or adolescents. It is intended exclusively for postmenopausal women.
Elderly Patients
No dosage adjustment is required for elderly patients. The standard adult dosing regimen applies. However, as with all HRT products, the lowest effective dose should be used for the shortest duration necessary. Regular medical review is particularly important in older patients, given the age-related increase in certain risk factors.
How to Use the Applicator
- Open the tube: Remove the cap and use its pointed tip to pierce the seal. Do not use if the seal is already broken.
- Prepare the applicator: Insert the white plunger fully into the applicator. Screw the applicator onto the tube opening.
- Fill the applicator: Squeeze the tube gently to fill the applicator with gel up to the fill mark. The plunger will stop at the mark automatically.
- Detach: Unscrew the applicator from the tube and replace the cap on the tube.
- Apply: Lie down in a comfortable position. Insert the end of the applicator deep into the vagina and press the plunger slowly until it reaches the bottom.
- Clean up: For single-use applicators: pull out the plunger, discard the applicator, and rinse the reusable plunger with warm, clean water. For reusable applicators: rinse both the applicator and plunger with warm, clean water.
Missed Dose
If you forget to apply a dose, apply it as soon as you remember, provided no more than 12 hours have elapsed since the missed dose. If more than 12 hours have passed, skip the missed dose and continue with your regular schedule. Do not apply a double dose to make up for a forgotten dose.
Overdose
Overdose from vaginal application is unlikely. If too much gel is applied on a single occasion, or if the gel is accidentally swallowed (e.g., by a child), there is generally no cause for alarm. However, contact your healthcare provider or poison control center for advice. Symptoms of ingestion may include nausea, vomiting, and in some cases, vaginal bleeding may occur after a few days.
What Are the Side Effects of Blissel?
The most common side effects of Blissel are local — itching and irritation in and around the vagina, which often resolve with continued use. Because Blissel has very low systemic absorption, the systemic side effects associated with oral HRT (such as blood clots and stroke) are considerably less likely.
Like all medicines, Blissel can cause side effects, although not everyone will experience them. During the initial phase of treatment, local irritation or itching may occur as the vaginal tissue begins to respond to the estrogen. In most patients, these effects diminish as treatment continues and the vaginal epithelium restores itself. Speak with your healthcare provider if any side effects become bothersome or persist.
Common
- Vaginal itching (pruritus)
- Local irritation in and around the vagina
Uncommon
- Lower abdominal pain
- Skin irritation
- Genital itching
- Headache
- Vaginal yeast infection (candidiasis)
Reported with systemic HRT (less likely with Blissel)
- Venous thromboembolism (blood clots in legs or lungs)
- Ovarian cancer
- Stroke
- Probable memory loss if HRT started after age 65
- Gallbladder disease
- Skin discoloration (chloasma)
- Erythema nodosum (painful reddish-purple skin lumps)
- Erythema multiforme (ring-shaped rashes or sores)
It is important to distinguish between side effects of Blissel (a locally acting vaginal estrogen) and those of systemic HRT. The risks of blood clots, stroke, breast cancer, and ovarian cancer are primarily associated with systemic HRT preparations (tablets, patches) that achieve higher estrogen levels in the blood. Because Blissel delivers a very low dose of estriol directly to the vaginal tissue with minimal systemic absorption, these risks are expected to be substantially lower. Nonetheless, you should contact your healthcare provider if you have any concerns.
If you experience any side effects, including those not listed above, you can report them to your national medicines regulatory authority. Reporting helps regulators continuously monitor the benefit-risk balance of medicines. In the UK, report via the Yellow Card Scheme; in the EU, through your national pharmacovigilance system; in the US, through the FDA MedWatch program.
How Should You Store Blissel?
Store Blissel at or below 25°C (77°F). Keep out of sight and reach of children. Do not use after the expiry date printed on the carton and tube label.
Proper storage of Blissel is essential to ensure the medicine remains effective and safe to use. Follow these storage guidelines:
- Temperature: Store at or below 25°C (77°F). Do not freeze.
- Children: Keep the tube and applicators out of the sight and reach of children at all times.
- Expiry date: Do not use Blissel after the expiry date stated on the carton and tube. The expiry date refers to the last day of that month.
- After opening: Use within the period specified on the packaging. Replace the cap securely after each use.
- Disposal: Do not dispose of medicines via wastewater or household waste. Ask your pharmacist how to dispose of medicines you no longer use. These measures help protect the environment.
What Does Blissel Contain?
Each gram of Blissel vaginal gel contains 50 micrograms (0.05 mg) of estriol as the active ingredient. The gel also contains excipients including glycerol, preservatives (sodium methylparaben and sodium propylparaben), polycarbophil, carbopol, sodium hydroxide, hydrochloric acid, and purified water.
Active Ingredient
One applicator dose delivers 1 g of vaginal gel containing 50 micrograms (0.05 mg) of estriol. Estriol is a naturally occurring, short-acting estrogen that is one of the three main estrogens produced by the human body. It has a weaker estrogenic effect than estradiol and estrone, which contributes to its favorable safety profile when used vaginally.
Excipients (Inactive Ingredients)
| Ingredient | Function | Note |
|---|---|---|
| Glycerol (E 422) | Humectant / moisturizer | Helps keep the gel moist |
| Sodium methylparaben (E 219) | Preservative | May cause allergic reactions (possibly delayed) |
| Sodium propylparaben (E 217) | Preservative | May cause allergic reactions (possibly delayed) |
| Polycarbophil | Bioadhesive polymer | Helps the gel adhere to vaginal walls |
| Carbopol (carbomer) | Gel-forming agent | Provides gel consistency |
| Sodium hydroxide | pH adjuster | Adjusts acidity of the gel |
| Hydrochloric acid | pH adjuster | Adjusts acidity of the gel |
| Purified water | Vehicle / solvent | Base of the gel formulation |
Blissel contains sodium methylparaben (E 219) and sodium propylparaben (E 217), which may cause allergic reactions (possibly delayed). Do not use this medicine if you are allergic to any of its ingredients. If you experience signs of an allergic reaction after application, discontinue use and consult your healthcare provider.
Appearance and Pack Sizes
Blissel is a colorless, nearly transparent vaginal gel supplied in an aluminum tube. It is available in the following pack sizes:
- 10 g tube with either 10 single-use applicators and 1 reusable plunger, or 1 reusable applicator and 1 reusable plunger
- 30 g tube with either 30 single-use applicators (3 blister packs of 10) and 1 reusable plunger, or 1 reusable applicator and 1 reusable plunger
Not all pack sizes may be marketed in every country.
Frequently Asked Questions About Blissel
Blissel is used to treat vaginal atrophy — a condition characterized by vaginal dryness, irritation, burning, and painful intercourse — caused by declining estrogen levels after menopause. It contains the hormone estriol, which acts locally in the vagina to restore moisture and elasticity to the vaginal tissue. Blissel may also help reduce the frequency of recurrent urinary tract infections associated with vaginal atrophy.
Most women begin to notice improvement in vaginal symptoms within 1–3 weeks of starting daily treatment. The initial 3-week daily dosing phase is designed to restore the vaginal epithelium, after which maintenance dosing (twice weekly) is usually sufficient to sustain the improvement. Individual responses may vary, and some women may need a longer initial treatment period. If you do not notice improvement after 3 weeks, consult your healthcare provider.
No. Blissel is contraindicated in women who have or have had breast cancer. While Blissel has very low systemic absorption, the safety of vaginal estriol in breast cancer survivors has not been conclusively established. If you are experiencing vaginal atrophy after breast cancer treatment, discuss non-hormonal alternatives — such as vaginal moisturizers, lubricants, or other treatments — with your oncologist or gynecologist.
Weight gain is not a listed side effect of Blissel. Because Blissel acts locally in the vagina with very low systemic absorption, it is unlikely to cause the systemic effects sometimes associated with oral hormone therapy. If you experience unexplained weight changes while using Blissel, consult your healthcare provider to explore other potential causes.
No. One of the advantages of Blissel over systemic estrogen therapy is that it does not require the addition of a progestogen to protect the uterine lining. This is because the estriol in Blissel has very low systemic absorption and does not significantly stimulate the endometrium. However, if you experience any unexpected vaginal bleeding while using Blissel, consult your healthcare provider, as this warrants further investigation.
Yes, you can have sexual intercourse while using Blissel. However, it is best to apply Blissel at bedtime and allow sufficient time for the gel to be absorbed before intercourse. If you use latex condoms or diaphragms, be aware that some vaginal products can weaken latex — consult your pharmacist about compatibility. As Blissel treats vaginal dryness and irritation, many women find that intercourse becomes more comfortable with continued use.
References
This article is based on the following peer-reviewed sources and international clinical guidelines:
- European Medicines Agency (EMA). Estriol – Summary of Product Characteristics (SmPC). European Public Assessment Reports. Available at: ema.europa.eu
- The North American Menopause Society (NAMS). “The 2020 Genitourinary Syndrome of Menopause Position Statement.” Menopause, 27(9), 976–992. doi:10.1097/GME.0000000000001609
- National Institute for Health and Care Excellence (NICE). Menopause: Diagnosis and Management. Clinical Guideline NG23. Updated 2019. Available at: nice.org.uk/guidance/ng23
- International Menopause Society (IMS). “Updated 2023 IMS Recommendations on Menopausal Hormone Therapy.” Climacteric, 26(1), 1–14.
- Lethaby A, et al. “Local oestrogen for vaginal atrophy in postmenopausal women.” Cochrane Database of Systematic Reviews. 2016;(8):CD001500. doi:10.1002/14651858.CD001500.pub3
- British National Formulary (BNF). Estriol – Vaginal Preparations. Available at: bnf.nice.org.uk
- World Health Organization (WHO). Model List of Essential Medicines. 23rd List, 2023. Available at: who.int/publications
- European Menopause and Andropause Society (EMAS). “EMAS clinical guide: Low-dose vaginal estrogens for postmenopausal vaginal atrophy.” Maturitas, 73(2), 148–154.
- Cardozo L, et al. “Meta-analysis of estrogen therapy in the management of urogenital atrophy in postmenopausal women.” Obstetrics & Gynecology, 92(4), 722–727.
- Rahn DD, et al. “Vaginal estrogen for genitourinary syndrome of menopause: A systematic review.” Obstetrics & Gynecology, 124(6), 1147–1156. doi:10.1097/AOG.0000000000000526
Editorial Team
This article has been written, reviewed, and fact-checked by the iMedic Medical Editorial Team, comprising licensed specialist physicians with expertise in gynecology, endocrinology, and pharmacology.
iMedic Medical Editorial Team — qualified healthcare professionals with clinical experience in women’s health and menopause management.
iMedic Medical Review Board — independent review by board-certified physicians following international guidelines (EMA, NICE, IMS/EMAS).
All medical claims are supported by peer-reviewed research and international clinical guidelines. Evidence graded according to the GRADE framework. Level 1A where applicable.
No pharmaceutical company funding or sponsorship. All content is editorially independent with no conflicts of interest.