testosterone undecanoate: prescribing and clinical use
Focused clinical detail for use alongside current product information, local policy and patient-specific assessment.
testosterone undecanoate: clinical details
Prescribing considerations
- Confirm compatible symptoms and testosterone deficiency using two separate blood measurements; investigate alternative causes before treatment.
- Assess prostate cancer risk before initiation.
- Use caution with hypertension, sleep apnoea, epilepsy, migraine, thrombophilia, ischaemic heart disease and cardiac, hepatic or renal impairment.
- Consider reversible suppression of spermatogenesis when fertility matters.
- Observe during and immediately after injection because pulmonary oil microembolism and anaphylactic reactions can occur.
Contraindications and cautions
- Known or suspected androgen-dependent prostate or male breast carcinoma
- Past or present liver tumour
- Hypersensitivity to testosterone undecanoate or an excipient
- Use in women, including during pregnancy or breastfeeding
Monitoring
- Clinical response and serum testosterone
- Haemoglobin, haematocrit and red-cell count
- Prostate and breast examination, with PSA where appropriate
- Blood pressure, oedema and cardiovascular status
- Liver function and lipid profile
- Glucose control in people receiving diabetes treatment
- Symptoms or signs of venous thromboembolism
Clinical pharmacology
The intramuscular oily depot gradually releases testosterone undecanoate. Serum esterases cleave it to testosterone and undecanoic acid; testosterone acts through androgen receptors and through conversion to dihydrotestosterone and oestradiol.
Formulation and product differences
- This single-use, oil-based intramuscular depot contains refined castor oil and benzyl benzoate. It requires slow, deep gluteal administration and differs operationally from topical or oral testosterone formulations.
testosterone undecanoate preparations and strengths
Injection
Route: Parenteral
Strengths: 1000 mg/4 mL
testosterone undecanoate interactions
Tell the prescriber about all medicines, particularly:
Coumarin oral anticoagulants, such as warfarin
Testosterone may increase anticoagulant activity and bleeding risk, so closer INR monitoring may be required when treatment starts or stops.
Insulin and other glucose-lowering medicines
Improved insulin sensitivity may lower glucose and alter the amount of diabetes treatment required.
SGLT2 inhibitors
Combined use may further increase red-cell count, so haemoglobin and haematocrit require monitoring.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.