Leuject (Leuprorelin)
GnRH agonist — Solution for injection 2 mg/ml
Quick Facts About Leuject
Key Takeaways About Leuject
- Hormone suppression therapy: Leuject works by suppressing testosterone and estrogen production to castrate or postmenopausal levels after an initial stimulation phase
- Initial flare effect: Symptoms may temporarily worsen during the first 1–2 weeks of treatment before improvement begins; anti-androgen cover may be needed in prostate cancer patients
- Multiple indications: Used for advanced prostate cancer, endometriosis, uterine fibroids, central precocious puberty, and assisted reproduction
- Regular monitoring required: Blood tests (PSA, testosterone/estrogen levels), bone density scans, and cardiovascular assessments are recommended during treatment
- Contraindicated in pregnancy: Leuject can cause fetal harm and must not be used during pregnancy; non-hormonal contraception is essential for women of childbearing age
What Is Leuject and What Is It Used For?
Leuject (leuprorelin acetate) is a synthetic GnRH agonist that suppresses the body's production of sex hormones. It is primarily used to treat advanced prostate cancer, endometriosis, uterine fibroids, and central precocious puberty in children.
Leuject belongs to the class of medicines known as gonadotropin-releasing hormone (GnRH) agonists. The active substance, leuprorelin acetate, is a synthetic analogue of the naturally occurring GnRH hormone produced by the hypothalamus. When administered continuously, leuprorelin causes the pituitary gland to become desensitized, leading to a significant reduction in the hormones that stimulate the gonads (testes in men and ovaries in women).
This medication is available as a 2 mg/ml solution for injection and is administered subcutaneously (under the skin). The daily injection formulation allows for precise dose adjustments and rapid discontinuation if needed, which may be particularly important in certain clinical situations such as assisted reproduction protocols.
The mechanism of action involves an initial paradoxical stimulation of the pituitary gland, known as the flare effect, which lasts approximately 1–2 weeks. During this phase, levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) temporarily increase, leading to a brief rise in testosterone (in men) or estrogen (in women). After this initial period, continuous exposure to the GnRH agonist causes downregulation and desensitization of GnRH receptors, resulting in a profound and sustained suppression of gonadotropin secretion. Within 2–4 weeks of treatment, testosterone levels in men typically fall to castrate levels (below 50 ng/dL), and estrogen levels in women decline to postmenopausal ranges.
Approved Indications
Leuject is approved for the treatment of several hormone-dependent conditions:
- Advanced prostate cancer: As hormonal therapy (androgen deprivation therapy) in men with metastatic or locally advanced prostate cancer, where testosterone suppression is the treatment goal
- Endometriosis: To reduce endometriotic lesions, relieve pelvic pain, and manage symptoms of endometriosis in women
- Uterine fibroids (leiomyomas): Preoperative treatment to reduce the size of fibroids and control bleeding before surgery, or as medical management in selected cases
- Central precocious puberty: Treatment of children with central (gonadotropin-dependent) precocious puberty to delay the progression of puberty until an appropriate age
- Assisted reproduction: As part of controlled ovarian stimulation protocols in women undergoing in vitro fertilization (IVF) or other assisted reproductive technologies
Leuject is a daily injection formulation (2 mg/ml solution), unlike depot formulations of leuprorelin (such as monthly or 3-monthly injections) that use slow-release technology. The daily formulation offers more flexibility in dosing and faster reversibility of hormonal effects upon discontinuation, which can be advantageous in certain clinical scenarios.
What Should You Know Before Taking Leuject?
Before starting Leuject, your doctor must assess your medical history, including cardiovascular health, bone density, and metabolic status. The medication is contraindicated in pregnancy and in patients with known hypersensitivity to GnRH agonists.
Leuject is a potent hormonal therapy that requires careful medical assessment before initiation. Your prescribing physician should conduct a thorough evaluation of your health status and review your complete medication list to identify potential contraindications and interactions. It is essential that you inform your doctor about all medical conditions, particularly heart disease, diabetes, liver or kidney problems, seizure disorders, and mental health conditions.
Contraindications
Leuject should not be used in the following situations:
- Hypersensitivity: Known allergy to leuprorelin, other GnRH agonists, or any of the excipients in the formulation
- Pregnancy: Leuprorelin is teratogenic and may cause spontaneous abortion; pregnancy must be excluded before starting treatment
- Breastfeeding: It is not known whether leuprorelin passes into breast milk; the potential risk to the infant precludes use during lactation
- Undiagnosed vaginal bleeding: The cause of abnormal vaginal bleeding must be established before starting GnRH agonist therapy
- Spinal cord compression or urinary tract obstruction: In prostate cancer patients at risk of neurological complications from tumor flare, treatment should be initiated with anti-androgen cover or an alternative approach such as a GnRH antagonist should be considered
Warnings and Precautions
Several important warnings apply to the use of Leuject. Patients and healthcare providers should be aware of the following considerations:
- Tumor flare phenomenon: During the first few weeks of treatment, the initial rise in testosterone can cause a temporary worsening of symptoms in prostate cancer patients, including increased bone pain, urinary obstruction, and in rare cases, spinal cord compression. Anti-androgen therapy (such as bicalutamide or flutamide) is often co-prescribed for the first 2–4 weeks to mitigate this effect.
- Cardiovascular risk: GnRH agonist therapy is associated with an increased risk of cardiovascular events, including myocardial infarction, stroke, and sudden cardiac death. Patients with pre-existing cardiovascular disease should be carefully monitored. Blood pressure, lipid profiles, and blood glucose should be checked regularly.
- Bone mineral density loss: Long-term testosterone or estrogen suppression leads to accelerated bone loss and increased fracture risk. Baseline and periodic bone density assessments (DEXA scans) are recommended. Calcium and vitamin D supplementation should be considered.
- Metabolic effects: Androgen deprivation therapy can lead to insulin resistance, hyperglycemia, weight gain, and changes in body composition. Patients with diabetes or prediabetes require closer glycemic monitoring.
- QT prolongation: Leuprorelin may prolong the QT interval. Caution is advised in patients with risk factors for QT prolongation, including those taking other QT-prolonging medications, patients with electrolyte imbalances, or those with a history of cardiac arrhythmias.
- Mood changes and depression: Hormonal suppression can cause significant mood alterations, including depression, irritability, and emotional lability. Patients should be monitored for mood changes, and those with a history of depression should be observed closely.
- Seizures: There have been rare reports of seizures in patients receiving GnRH agonists. Patients with a history of seizures or conditions that predispose to seizures should be monitored accordingly.
Pregnancy and Breastfeeding
Leuject is classified as Category X in pregnancy, meaning it is absolutely contraindicated. Animal studies and the known pharmacological effects of leuprorelin confirm the risk of fetal harm, including increased rates of fetal death and developmental abnormalities. Women of childbearing potential must use effective non-hormonal contraception (such as barrier methods or copper IUD) during treatment and for a specified period after discontinuation, as hormonal contraceptives may not be effective during GnRH agonist therapy.
A pregnancy test should be performed before starting Leuject. If pregnancy occurs during treatment, the medication must be discontinued immediately, and the patient should be informed of the potential risk to the fetus. Breastfeeding mothers should not use Leuject, as it is unknown whether leuprorelin or its metabolites are excreted in human milk.
In patients with prostate cancer, the initial flare effect can cause serious complications including spinal cord compression, ureteral obstruction, and acute urinary retention. These complications can lead to paralysis or renal failure if not recognized and treated promptly. Patients should be closely monitored during the first few weeks of treatment, and anti-androgen cover should be considered.
How Does Leuject Interact with Other Drugs?
Leuject may interact with medications that affect the QT interval, blood sugar levels, or bone metabolism. Patients should inform their doctor about all prescription and over-the-counter medications, including herbal supplements.
While formal drug interaction studies with leuprorelin are limited, several clinically significant interactions have been identified through post-marketing surveillance and pharmacological considerations. The hormonal suppression caused by Leuject can alter the metabolism and effects of other medications, and certain drugs may interfere with the therapeutic effects of leuprorelin.
It is particularly important to inform your healthcare provider if you are taking any of the following categories of medications. Drug interaction management may require dose adjustments, enhanced monitoring, or alternative therapeutic choices.
Major Interactions
| Interacting Drug/Class | Effect | Clinical Management |
|---|---|---|
| QT-prolonging drugs (e.g., amiodarone, sotalol, haloperidol, ondansetron) | Additive QT prolongation risk; increased risk of torsades de pointes and cardiac arrhythmias | ECG monitoring recommended; correct electrolyte imbalances; consider alternative agents |
| Anti-androgens (bicalutamide, flutamide, enzalutamide) | Intentional co-administration during flare period; enhanced androgen blockade | Monitor liver function; typically used for first 2–4 weeks of treatment to prevent flare complications |
| Hormonal contraceptives | Reduced efficacy of hormonal contraception due to altered hormonal milieu | Use non-hormonal contraception (barrier methods, copper IUD) during treatment |
Minor Interactions
| Interacting Drug/Class | Effect | Clinical Management |
|---|---|---|
| Hypoglycemic agents (insulin, metformin, sulfonylureas) | GnRH agonists may worsen insulin resistance and impair glycemic control | Monitor blood glucose more frequently; adjust diabetes medication doses as needed |
| Anticoagulants (warfarin, heparin) | Altered coagulation parameters reported with concurrent GnRH agonist use | Monitor INR/coagulation more frequently during initiation and dose changes |
| Bisphosphonates (alendronate, zoledronic acid) | Often co-prescribed to counteract GnRH agonist-induced bone loss; no antagonistic interaction | Consider bone-protective therapy in patients on long-term GnRH agonist treatment |
| Corticosteroids | Additive bone mineral density loss with concurrent long-term use | Monitor bone density; ensure adequate calcium and vitamin D supplementation |
What Is the Correct Dosage of Leuject?
Leuject dosage varies by indication. For prostate cancer, the typical dose is 1 mg (0.5 ml) subcutaneously once daily. For endometriosis and fibroids, the dose is typically 1 mg daily for up to 6 months. All doses must be prescribed and monitored by a specialist physician.
The dosage of Leuject depends on the specific clinical indication, patient characteristics, and treatment goals. The 2 mg/ml solution for injection allows flexible dosing across different indications. Treatment should always be initiated and monitored by a specialist physician experienced in the management of the relevant condition. Subcutaneous injection sites should be rotated to prevent injection site reactions and lipoatrophy.
Adults
| Indication | Dosage | Duration | Notes |
|---|---|---|---|
| Advanced prostate cancer | 1 mg (0.5 ml) subcutaneously once daily | Long-term / continuous | Anti-androgen cover recommended for first 2–4 weeks; monitor PSA and testosterone levels |
| Endometriosis | 1 mg (0.5 ml) subcutaneously once daily | Up to 6 months | Add-back therapy with low-dose estrogen/progestogen may allow extension to 12 months; reassess bone density |
| Uterine fibroids | 1 mg (0.5 ml) subcutaneously once daily | 3–6 months preoperatively | Goal is fibroid volume reduction before surgery; monitor hemoglobin levels |
| Assisted reproduction (IVF) | 0.5–1 mg (0.25–0.5 ml) subcutaneously once daily | Until pituitary suppression achieved | Dose and duration determined by fertility specialist based on protocol (long or short) |
Children
Central Precocious Puberty
In children diagnosed with central (gonadotropin-dependent) precocious puberty, the dosage of Leuject is individualized based on body weight and clinical response. The typical starting dose ranges from 20–50 micrograms/kg/day administered subcutaneously. The dose is adjusted based on suppression of gonadotropins and sex steroids, monitored through regular blood tests and clinical assessment of pubertal progression.
Treatment is continued until the appropriate age for puberty onset has been reached, at which point the medication is discontinued to allow natural puberty to proceed. Regular monitoring of growth velocity, bone age, and hormonal levels is essential throughout treatment.
Elderly
Elderly Patients (65 years and older)
No specific dose adjustment is required for elderly patients based on age alone. However, elderly patients are more likely to have impaired renal or hepatic function and cardiovascular comorbidities. Given the increased cardiovascular risk associated with GnRH agonist therapy, elderly patients with advanced prostate cancer should undergo careful cardiovascular risk assessment before and during treatment. More frequent monitoring of blood pressure, lipid profiles, blood glucose, and bone density is recommended in this population.
Missed Dose
If you miss a dose of Leuject, take it as soon as you remember on the same day. If it is almost time for your next scheduled dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you miss several consecutive doses, contact your healthcare provider, as the effectiveness of hormonal suppression may be compromised.
Consistent daily dosing is important for maintaining adequate suppression of gonadotropins and sex hormones. Irregular dosing may lead to incomplete suppression and a potential resurgence of hormone-dependent disease activity.
Overdose
There is limited experience with overdose of leuprorelin in clinical settings. In animal studies, high doses of GnRH agonists did not produce acute toxicity. Symptoms of overdose may include enhanced pharmacological effects such as deepening of hormone suppression. In the event of a suspected overdose, contact your healthcare provider or poison control center immediately. Treatment is symptomatic and supportive, as there is no specific antidote for leuprorelin.
Rotate injection sites between the abdomen (at least 2 inches from the navel), upper thighs, and upper arms. Clean the injection site with an alcohol swab and allow it to dry before injecting. Pinch the skin and insert the needle at a 45-degree angle. After injection, do not rub the site. Store unused solution in the refrigerator as directed.
What Are the Side Effects of Leuject?
The most common side effects of Leuject include hot flushes, sweating, decreased libido, erectile dysfunction (in men), injection site reactions, and fatigue. Most side effects are related to the suppression of sex hormones and are generally reversible upon discontinuation.
Like all medicines, Leuject can cause side effects, although not everybody gets them. The side effects of leuprorelin are primarily a consequence of its pharmacological action — the suppression of sex hormone production. Many of these effects are predictable and manageable with appropriate supportive care. The severity and frequency of side effects may vary depending on the dose, duration of treatment, and individual patient factors.
It is important to distinguish between side effects that are expected and generally manageable, and those that require immediate medical attention. Report any new or worsening symptoms to your healthcare provider promptly, especially during the first few weeks of treatment when the flare effect may occur.
Very Common (affects more than 1 in 10 patients)
- Hot flushes and sweating (experienced by up to 80% of patients)
- Injection site reactions (pain, redness, swelling at injection site)
- Fatigue and general weakness
- Decreased libido (reduced sexual desire)
- Erectile dysfunction (in male patients)
- Headache
- Mood changes, irritability
Common (affects 1 to 10 in 100 patients)
- Nausea and gastrointestinal discomfort
- Joint and muscle pain (arthralgia, myalgia)
- Depression and emotional lability
- Insomnia and sleep disturbances
- Weight gain and peripheral edema
- Dizziness
- Skin rash, itching, or acne
- Breast tenderness or gynecomastia (in men)
- Vaginal dryness and dyspareunia (in women)
- Bone and back pain (including initial flare in prostate cancer patients)
Uncommon (affects 1 to 10 in 1,000 patients)
- Palpitations and tachycardia
- Hypertension (elevated blood pressure)
- Changes in blood glucose levels (hyperglycemia)
- Memory impairment and cognitive changes
- Paresthesia (tingling or numbness)
- Visual disturbances
- Hair loss (alopecia)
- Testicular atrophy (with prolonged use)
Rare (affects fewer than 1 in 1,000 patients)
- Anaphylactic/anaphylactoid reactions
- QT interval prolongation
- Seizures or convulsions
- Pulmonary embolism
- Spinal cord compression (in prostate cancer patients with vertebral metastases)
- Interstitial lung disease
- Pituitary apoplexy (in patients with pituitary adenoma)
- Severe liver dysfunction
Sudden severe headache, visual changes, confusion, or collapse (signs of pituitary apoplexy); difficulty breathing or chest tightness (possible anaphylaxis or pulmonary embolism); sudden weakness or numbness in the legs, loss of bladder or bowel control (signs of spinal cord compression); or severe irregular heartbeat (QT prolongation). These are rare but potentially life-threatening complications requiring emergency treatment.
How Should You Store Leuject?
Leuject should be stored in a refrigerator at 2–8°C, protected from light. Do not freeze. Keep the medicine out of the reach of children and do not use after the expiry date.
Proper storage of Leuject is essential to maintain the stability and effectiveness of the medication. The leuprorelin solution is sensitive to temperature and light exposure, and improper storage may result in degradation of the active substance, potentially reducing the therapeutic effect or causing adverse reactions.
- Temperature: Store in a refrigerator at 2–8°C (36–46°F). Do not freeze the solution, as freezing may alter the formulation and render it unsuitable for use.
- Light protection: Keep the vials or pre-filled syringes in the original packaging to protect from light exposure.
- Room temperature: If needed, Leuject may be kept at room temperature (up to 25°C / 77°F) for a short period (typically up to 4 weeks), but should not be returned to the refrigerator after being stored at room temperature.
- Expiry date: Do not use Leuject after the expiry date stated on the packaging. The expiry date refers to the last day of that month.
- Disposal: Do not dispose of used needles or syringes in household waste. Use an approved sharps disposal container and return it to your pharmacy or healthcare provider for safe disposal.
- Visual inspection: Before each use, inspect the solution for discoloration, particulate matter, or crystallization. Do not use if the solution appears cloudy, discolored, or contains visible particles.
Keep Leuject out of the sight and reach of children. Do not store it in a bathroom or near a kitchen sink where it might be exposed to moisture and heat. If you have any unused or expired medication, ask your pharmacist about the proper method of disposal.
What Does Leuject Contain?
Each milliliter of Leuject solution contains 2 mg of leuprorelin acetate as the active ingredient. The solution also contains excipients that maintain stability and pH.
Understanding the composition of Leuject is important for patients with known allergies to specific excipients or pharmaceutical ingredients. The formulation is designed to provide a stable, injectable solution suitable for subcutaneous administration.
Active Ingredient
- Leuprorelin acetate: 2 mg per ml of solution. Leuprorelin acetate is the acetate salt of leuprorelin, a synthetic nonapeptide analogue of naturally occurring gonadotropin-releasing hormone (GnRH). It has a molecular formula of C59H84N16O12 and is approximately 15–20 times more potent than natural GnRH.
Excipients
The solution for injection typically contains the following inactive ingredients (excipients), which serve various pharmaceutical functions:
- Sodium chloride: An isotonicity agent that makes the solution compatible with body tissues
- Acetic acid (glacial): Used for pH adjustment
- Sodium acetate trihydrate: Acts as a buffer to maintain solution stability
- Water for injections: The vehicle (solvent) for the solution
The solution is preservative-free in single-dose presentations. Patients with known allergies to any of these components should inform their healthcare provider before starting treatment. The exact composition may vary between manufacturers; always consult the patient information leaflet provided with your specific product for the complete list of ingredients.
Frequently Asked Questions About Leuject
Leuject (leuprorelin) is a GnRH agonist used primarily for the treatment of advanced prostate cancer, endometriosis, uterine fibroids, central precocious puberty in children, and as part of assisted reproduction protocols (IVF). It works by suppressing the production of sex hormones (testosterone and estrogen) through pituitary desensitization, making it effective for conditions that are driven by or responsive to hormonal manipulation.
Leuject begins to affect hormone levels immediately, but the full therapeutic effect takes 2–4 weeks. During the first 1–2 weeks, an initial flare effect occurs where hormone levels temporarily increase before declining. Testosterone in men typically reaches castrate levels (below 50 ng/dL) within 2–4 weeks of continuous daily treatment. For conditions like endometriosis, symptom relief may take 4–8 weeks to become apparent.
The flare effect is a temporary increase in sex hormone levels (testosterone or estrogen) that occurs during the first 1–2 weeks of GnRH agonist treatment. This is a predictable pharmacological response, as the drug initially stimulates the pituitary gland before causing desensitization. In prostate cancer patients, this can temporarily worsen symptoms like bone pain or urinary difficulty. Your doctor may prescribe anti-androgen medication during this period to minimize flare-related complications. After 2–4 weeks, hormone levels will fall to very low levels.
No, Leuject is strictly contraindicated during pregnancy (Category X). Leuprorelin can cause fetal harm, including spontaneous abortion and developmental abnormalities. Women of childbearing potential must use effective non-hormonal contraception during treatment. A pregnancy test should be performed before starting therapy, and treatment must be stopped immediately if pregnancy is suspected.
In most cases, fertility recovers after discontinuation of Leuject. For the daily injection formulation, hormone levels typically begin to recover within a few weeks of stopping treatment. In women, menstruation usually returns within 1–3 months. However, recovery time can vary between individuals. In men who have been on long-term androgen deprivation therapy, testosterone recovery may take several months to a year. Your healthcare provider can monitor hormone levels and advise on expected timelines for fertility recovery.
Leuject is injected subcutaneously (under the skin), typically in the abdomen, upper thigh, or upper arm. Clean the injection site with an alcohol swab, pinch the skin, insert the needle at a 45-degree angle, and inject the solution slowly. Rotate injection sites to prevent irritation. Your healthcare provider or nurse will demonstrate the proper technique. Store the medication in the refrigerator and inspect the solution before each use — do not use if it appears cloudy or contains particles.
References
This article is based on peer-reviewed medical literature and international guidelines. All medical claims have evidence level 1A (systematic reviews and randomized controlled trials).
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- Keating NL, O'Malley AJ, Smith MR. Diabetes and cardiovascular disease during androgen deprivation therapy for prostate cancer. Journal of Clinical Oncology. 2006;24(27):4448–4456. doi:10.1200/JCO.2006.06.2497
- Shahinian VB, Kuo YF, Freeman JL, Goodwin JS. Risk of fracture after androgen deprivation for prostate cancer. New England Journal of Medicine. 2005;352(2):154–164. doi:10.1056/NEJMoa042671
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