Androgen Receptor Inhibitor Pregnancy: Not for use in women; contraindicated in women who are or may become pregnant (may cause fetal harm or loss of pregnancy). A condom is required during and for 3 months after treatment if engaged in sexual activity with a pregnant woman; a condom plus another form of birth control if the partner is of childbearing potential.

Enzalutamide

Brand names: Xtandi

Enzalutamide is an oral androgen receptor signalling inhibitor used across hormone-sensitive and castration-resistant prostate cancer, given with ongoing androgen deprivation therapy.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 160 mg

Route: Oral

Frequency: Once daily

Recommended dose is 160 mg (four 40 mg film-coated tablets) as a single oral daily dose, with or without food; tablets swallowed whole (not cut, crushed or chewed). Treatment should be initiated and supervised by specialists experienced in prostate cancer treatment. Medical castration with an LHRH analogue should be continued during treatment of CRPC or mHSPC patients who are not surgically castrated; high-risk BCR nmHSPC may be treated with or without an LHRH analogue. For >= Grade 3 toxicity or intolerable adverse reaction, withhold dosing for one week or until symptoms improve to <= Grade 2, then resume at same or reduced dose (120 mg or 80 mg). With a strong CYP2C8 inhibitor (avoid if possible), reduce enzalutamide to 80 mg once daily. No dose adjustment for elderly, hepatic impairment (Child-Pugh A, B or C), or mild/moderate renal impairment; caution in severe renal impairment or end-stage renal disease.

Dose adjustments

Renal

No dose adjustment for mild or moderate renal impairment; caution in severe renal impairment or end-stage renal disease.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance or any excipient
Women who are or may become pregnant

Side effects

Asthenia / fatigue
Hot flush
Hypertension
Fractures and falls
Headache
Ischaemic heart disease; seizure (uncommon)

Interactions

Avoid concomitant strong CYP2C8 inhibitors; if unavoidable, reduce enzalutamide to 80 mg once daily
Potent enzyme inducer - may reduce efficacy of many co-administered medicines that are sensitive substrates of metabolising enzymes/transporters
Avoid co-administration with warfarin and coumarin-like anticoagulants; if co-administered with a CYP2C9-metabolised anticoagulant (warfarin, acenocoumarol), conduct additional INR monitoring

Clinical monograph

How it works

It competitively inhibits androgen binding to the receptor and blocks receptor nuclear translocation and DNA binding, suppressing androgen-driven tumour growth.

Prescribing in practice

It lowers the seizure threshold, so caution and careful assessment are needed in patients with a history of seizures or predisposing factors.
Fatigue, hypertension, falls and fractures are recognised adverse effects requiring monitoring and fall-risk reduction.
As a strong enzyme inducer it has numerous clinically important drug interactions that should be reviewed.

Monitoring

Monitor blood pressure, prostate-specific antigen response, falls and fracture risk, and review for neurological symptoms during treatment.

Counselling the patient

Continue your hormone (androgen deprivation) treatment alongside these tablets.
Report any blackout, fit or new severe headache promptly.
Take care to avoid falls, and tell your team about all other medicines you take.

Evidence & guidelines

Trials including AFFIRM, PREVAIL, ARCHES and ENZAMET established enzalutamide's survival benefit across the prostate cancer disease spectrum.

Reference: NICE TA580; AFFIRM trial; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways