Boldenone Undecylenate 250 mg/ml

Boldenone Undecylenate 250 mg/ml (Boldenone)

Anabolic steroid · very-long-acting ester

Each 1 ml contains Boldenone Undecylenate 250 mg in a sterile oil carrier.

For the full list of excipients, see section 6.1.

Solution for injection in a single-use glass ampoule for deep intramuscular use.

Therapeutic indications

Anabolic therapy with an extended release profile, as determined by a physician.

Posology and method of administration

Deep intramuscular injection as directed by a physician. Not for intravenous use. Rotate injection sites. Dose and interval are individualised by the prescriber.

Contraindications

Known hypersensitivity to the active substance or excipients. Known or suspected carcinoma of the prostate or male breast. Not for use in women, in pregnancy or while breastfeeding. Use with caution in cardiac, renal or hepatic impairment.

Special warnings and precautions for use

Keep out of the reach and sight of children. Contains a substance prohibited in sport (WADA).

Interaction with other medicinal products

Coumarin anticoagulants (warfarin)

Androgens potentiate anticoagulation, prolonging prothrombin time and INR and increasing the bleeding risk; the very long depot half-life means the effect persists for weeks after the last injection, so coagulation monitoring must continue well beyond discontinuation.

Insulin and oral antidiabetic agents

Improved insulin sensitivity and lowered blood glucose may precipitate hypoglycaemia and reduce antidiabetic requirements; glycaemic monitoring is required, with review of therapy by the prescriber.

Aromatase inhibitors (anastrozole, letrozole) and selective oestrogen receptor modulators (tamoxifen)

Genuine pharmacodynamic interaction: because boldenone is aromatised to 1-dehydro-oestradiol, aromatase inhibition reduces circulating oestrogen and attenuates oestrogen-mediated effects, while further lowering high-density lipoprotein cholesterol and, with prolonged use, adversely affecting bone mineral density.

5-alpha reductase inhibitors (finasteride, dutasteride)

Reduce conversion of boldenone to the more potent androgen 1-testosterone and may therefore attenuate androgen-mediated effects on prostate, skin and scalp, without affecting aromatisation or the systemic anabolic action.

Corticosteroids and corticotrophin

Additive sodium and fluid retention with an increased risk of oedema and worsening hypertension, particularly relevant given the oestrogenic fluid retention already associated with boldenone.

Use in special populations

Pregnancy and breastfeeding

Contraindicated. Boldenone crosses the placenta and may cause virilisation of a female foetus; the extremely long depot residence means exposure persists for months after the final injection, which must be taken into account when pregnancy is planned. Breastfeeding is not recommended, as excretion into human milk and effects on the infant are not established.

Paediatric population

Not recommended. Androgens accelerate epiphyseal maturation and may cause premature epiphyseal closure with irreversible loss of adult height, and precocious virilisation; the long duration of action makes the effects difficult to reverse should they occur.

Elderly

Increased susceptibility to prostatic hyperplasia and to unmasking of occult prostatic carcinoma, and reduced tolerance of erythrocytosis, fluid retention and hypertension. Contraindicated in carcinoma of the prostate or of the male breast; prostate status, haematocrit and cardiovascular parameters should be reviewed periodically.

Renal impairment

Use with caution. Sodium and water retention, accentuated by the oestrogenic metabolite, may precipitate or worsen oedema, hypertension and cardiac failure. No dedicated pharmacokinetic data exist in renal impairment; monitoring of weight, blood pressure and electrolytes is appropriate.

Hepatic impairment

Contraindicated in severe hepatic impairment. In mild to moderate impairment, hepatic metabolism of boldenone and clearance of its oestrogenic metabolite may be reduced, so liver function should be monitored; hepatic risk is nevertheless far lower than with 17-alpha-alkylated oral androgens.

Athletes

Boldenone is prohibited at all times, in and out of competition, under class S1.1a (exogenous anabolic androgenic steroids) of the World Anti-Doping Agency Prohibited List. It is one of the most persistently detectable agents in this class: characteristic urinary metabolites, confirmed where necessary by isotope ratio mass spectrometry to distinguish exogenous administration from endogenous or dietary sources, have been reported for several months after a single undecylenate injection. Use by athletes subject to anti-doping regulation is not permissible other than under a granted therapeutic use exemption.

Undesirable effects

Endocrine and reproductive

Suppression of luteinising hormone and follicle-stimulating hormone with reduced endogenous testosterone, testicular atrophy, oligospermia or azoospermia and impaired fertility; gynaecomastia and mastodynia secondary to aromatisation to 1-dehydro-oestradiol; in women, virilisation with hirsutism, voice deepening, clitoromegaly and menstrual disturbance

Blood and lymphatic system

Marked increases in haemoglobin, haematocrit and red cell mass, erythrocytosis with raised blood viscosity and an associated risk of thromboembolic events; boldenone is among the more strongly erythropoietic anabolic androgens

Metabolism, nutrition and investigations

Increased appetite and weight gain, sodium and water retention, decreased high-density lipoprotein cholesterol with increased low-density lipoprotein cholesterol, suppressed sex hormone-binding globulin, raised oestradiol-equivalent oestrogen concentrations

Cardiovascular

Hypertension, peripheral oedema, palpitations; with prolonged high exposure, left ventricular hypertrophy and impaired cardiac function

Skin and subcutaneous tissue

Acne, seborrhoea, oily skin, hirsutism, androgenetic alopecia in predisposed individuals; androgenic skin reactions may be accentuated by 5-alpha-reduction to 1-testosterone

Psychiatric

Irritability, aggression, restlessness, anxiety, mood lability and insomnia; depressed mood and reduced libido on withdrawal of prolonged treatment

Hepatobiliary

Transient elevation of transaminases; serious hepatic reactions are uncommon with this non-17-alpha-alkylated parenteral ester, in contrast to the cholestasis, peliosis hepatis and hepatic tumours associated with 17-alpha-alkylated oral androgens

General disorders and administration site conditions

Injection site pain, induration and erythema, which may be prolonged because of the large oil volume and viscous ester; rarely sterile abscess; very rarely cough, dyspnoea or transient chest discomfort immediately after injection consistent with pulmonary oil microembolism

Overdose

Acute overdose is unlikely to be life-threatening but produces an exaggeration of the known androgenic, oestrogenic and haematological effects, notably erythrocytosis, oedema, hypertension and gynaecomastia. No specific antidote is available and the offending depot cannot be removed once injected, so effects may persist for several months. Management is discontinuation with symptomatic and supportive care, including monitoring of haematocrit, blood pressure, lipids and the gonadal axis, with venesection considered where erythrocytosis is severe.

Pharmacodynamic properties

Boldenone undecylenate is the undecylenate (undec-10-enoate) ester of boldenone, 1-dehydrotestosterone (androsta-1,4-diene-3-one-17-beta-ol), an anabolic-androgenic steroid differing from testosterone only by the additional 1,2-double bond. Liberated boldenone is a full agonist at the androgen receptor, promoting nitrogen retention, skeletal muscle protein synthesis, erythropoiesis and appetite, with androgenic activity approximately half that of testosterone at comparable anabolic effect. Unlike the dihydrotestosterone-derived androstane steroids, boldenone retains the 4-ene-3-one A-ring and is therefore a substrate both for aromatase, being converted to the oestrogen 1-dehydro-oestradiol at roughly half the rate at which testosterone is aromatised to oestradiol, and for 5-alpha-reductase, being converted to 1-testosterone (dihydroboldenone), a more potent androgen. Oestrogenic effects such as gynaecomastia and fluid retention are consequently possible, though less frequent than with equipotent doses of testosterone. Boldenone is not 17-alpha-alkylated. Gonadotrophin secretion is suppressed dose-dependently, with reduction of endogenous testosterone production.

Pharmacokinetic properties

The undecylenate ester carries an eleven-carbon unsaturated side chain, making the molecule highly lipophilic and giving the slowest depot release of the commonly used androgen esters. After deep intramuscular injection into the oily vehicle, the ester is released over several weeks and hydrolysed by non-specific esterases to boldenone and undecylenic acid; serum concentrations rise gradually over the first week and are sustained thereafter, so absorption governs disposition and the apparent terminal half-life is of the order of 14 days. Boldenone is highly protein bound, of the order of 98%, to sex hormone-binding globulin and albumin. It is metabolised by aromatisation to 1-dehydro-oestradiol, by 5-alpha-reduction to 1-testosterone and thence to androstanediol metabolites, and by 17-beta-oxidation to androsta-1,4-diene-3,17-dione, with urinary excretion predominantly as glucuronide conjugates. Because of the size of the depot and the lipophilicity of the ester, boldenone metabolites remain detectable in urine for many months after the last administration.

List of excipients

Benzyl benzoate 200 mg (co-solvent, required to hold the active in solution at 250 mg/ml), benzyl alcohol (E 1519) 30 mg (co-solvent and antimicrobial preservative), butylated hydroxytoluene (E 321) 0.1 mg (antioxidant), nitrogen (headspace overlay), refined oil carrier q.s. to 1 ml. The oil carrier is a pharmacopoeial refined vegetable oil for parenteral use complying with the current Ph. Eur./USP monograph.

Excipient warnings

This medicinal product contains 200 mg benzyl benzoate and 30 mg benzyl alcohol in each 1 ml ampoule. Benzyl benzoate may cause mild local irritation and, in the concentration used here, contributes to injection-site discomfort; benzyl alcohol may cause allergic reactions. Neither excipient should be given to newborn infants (up to 4 weeks of age), and the product should not be used for more than one week in infants and children under 3 years of age without medical advice, because of the risk of severe adverse reactions including metabolic acidosis and gasping syndrome. Benzyl alcohol and benzyl benzoate may accumulate in patients with hepatic or renal impairment; medical advice should be sought before use in such patients and in pregnancy or breast-feeding. This medicinal product also contains a refined vegetable oil carrier; rare hypersensitivity reactions to vegetable oils used as injection vehicles have been reported, and it must not be used in patients with known hypersensitivity to the oil carrier.

Incompatibilities

In the absence of compatibility studies, this medicinal product must not be mixed with other medicinal products. The benzyl benzoate–oil vehicle is immiscible with aqueous injections and infusion fluids and must not be diluted or combined in the same syringe with aqueous preparations, which would cause the active to precipitate. Intravenous administration is contraindicated; the product is for deep intramuscular injection only. Contact with plasticised PVC administration sets should be avoided, as benzyl benzoate may extract plasticiser from PVC.

Shelf life

36 months from the date of manufacture in the unopened container. Do not use after the expiry date stated on the ampoule and carton; the expiry date refers to the last day of that month.

After first opening

Single-use ampoule. Because of the high concentration the solution is viscous — allow the ampoule to reach room temperature before withdrawal and use a wider-bore needle to draw the dose, changing the needle before injection. Administer immediately after opening and discard any remaining solution; opened ampoules must never be retained or pooled. Inspect before use: the solution should be clear to slightly viscous, free from visible particles and free from crystalline deposit. If the product has been stored cool, crystals may separate; such ampoules must be discarded.

Storage

Store below 25 °C. Protect from light. Do not freeze. Keep ampoules in the outer carton until use.

Container

Clear or amber USP/Ph. Eur. Type I borosilicate glass one-point-cut ampoule, 1 ml nominal fill, fusion-sealed under a nitrogen headspace to limit oxidation of the oil carrier and co-solvent. Ten ampoules in a moulded tray within a printed folding carton with the package leaflet; the carton carries a GS1 DataMatrix encoding GTIN, batch, expiry and unique serial number, and a scratch-off verification panel. Primary packaging components are controlled under ISO 15378. Pack size: 10 ampoules × 1 ml.

Disposal

Any unused medicinal product or waste material should be disposed of in accordance with local requirements. Ampoules, needles and syringes must be placed immediately into an approved rigid sharps container; broken glass must not be discarded with domestic waste. Owing to the benzyl benzoate content, the solution must not be emptied into drains, wastewater or surface water.

Pack

10 Ampoules × 1 ml

GTIN

05012345678903

Serial

3310 4482 9061 03

LOT

BU2603C

MFG

03 / 2026

EXP

03 / 2029

Every carton carries a GS1 DataMatrix and a verification code; a pack can be checked at ergopharm.net/verify.

Ergopharm Advanced Research Centre, Tandalja, Vadodara, Gujarat 390012, India. For Export Only.

Report a suspected adverse reaction or quality defect to pv@ergopharm.net.