PharmaceuticalNon-steroidalAnti-androgenAndrogen-receptor antagonist

Bicalutamide

Also known as Casodex · ICI-176334

Written by enwyReviewed 15 Jul 20261 sources0 comments

Bicalutamide is a non-steroidal androgen-receptor antagonist widely used to treat prostate cancer and, off-label, in feminising hormone therapy and severe hirsutism. It blocks androgens at the receptor without lowering testosterone, and among older anti-androgens has a comparatively favourable side-effect profile aside from a risk of hepatotoxicity.

01 Overview

Approved as Casodex for prostate cancer, bicalutamide is one of the best-studied AR antagonists. It is also used off-label by transfeminine people and for androgen-dependent conditions because it produces strong AR blockade with fewer effects than flutamide.

In men not on androgen deprivation, AR blockade raises LH and testosterone and commonly causes gynecomastia and breast tenderness. Rare but serious hepatotoxicity mandates liver monitoring.

02 Mechanism

Competitively binds the androgen receptor, preventing testosterone and DHT from activating it. As a pure antagonist it does not lower serum androgens by itself, so in men it can raise testosterone via feedback.

03 Dosing

Tier	Dose	Route	Notes
Feminising (off-label)	25–50 mg/day	Oral	Off-label anti-androgen dose in HRT
Prostate cancer	50–150 mg/day	Oral	50 mg with LHRH analogue; 150 mg as monotherapy

04 Effects

Effect	Magnitude	Evidence
Androgen-receptor blockadeSuppresses androgen-driven prostate growth and, off-label, virilising features.	Strong	Clinical
Feminising effect (off-label)In transfeminine HRT, reduces androgen action to support feminisation.	Variable	Observational

05 Side effects

Effect	Severity	Frequency	Evidence
Gynecomastia and breast tendernessBreast growth and tenderness, especially in monotherapy where estrogen action is unopposed.	Moderate	Very common	Clinical
HepatotoxicityElevated transaminases and, rarely, serious liver injury.	Severe	Uncommon	Clinical
Hot flushes and fatigueVasomotor symptoms and tiredness from altered androgen signalling.	Mild	Common	Clinical

06 Legal status

United States

FDA-approved prescription drug

Approved for prostate cancer · as of Jan 2026

Prescription medicine

as of Jan 2026

07 References

Bicalutamide: a review of its use in advanced prostate cancerDrugs, 2004

08 Discussion0 comments

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This page is reference information, not medical advice. Doses and protocols are documented as they appear in the clinical literature and in practice — describing them is not a recommendation to use them. Countermeasures listed here are not a substitute for a physician. Legal status varies by jurisdiction and changes.