Bicalutamide

SOURCE: eMC UK SPC, productName 'Bicalutamide 150 mg film-coated Tablets' (https://www.medicines.org.uk/emc/product/101113/smpc), §4.2. VERBATIM: 'Adult males including older people: the dosage is one 150mg film-coated tablet to be taken orally once a day. Bicalutamide should be taken continuously for at least 2 years or until disease progression.' INDICATION QUALIFIER — READ BEFORE USE: the 150 mg strength above is the monotherapy product. A DIFFERENT regimen exists for combined androgen blockade: the US prescribing information fetched in this same bundle (bicalutamide, Proficient Rx LP, DailyMed, 2024-03-01) states 'The recommended dose for bicalutamide tablets therapy in combination with an LHRH analog is one 50 mg tablet once daily (morning or evening), with or without food', taken at the same time each day and started at the same time as treatment with the LHRH analogue. The UK SPC for the 50 mg product was NOT fetched in this bundle, so the 50 mg combined-blockade regimen is NOT asserted here for UK use — source that SPC separately. The two regimens differ threefold; confirm which indication and strength applies before acting on this page. INITIATION should be under the direct supervision of a specialist. For patients who have objective progression of disease together with elevated PSA, cessation of bicalutamide therapy should be considered. HEPATIC: no dose adjustment for mild hepatic impairment; increased accumulation may occur in moderate to severe hepatic impairment, so use with caution and consider periodic liver function testing (the majority of changes are expected within the first 6 months) and discontinue if changes are severe. The US label states no dosage adjustment is necessary in mild to moderate hepatic impairment, and none in severe impairment despite a 76% increase in the half-life of the active enantiomer. PHOTOSENSITIVITY (§4.4, reported for the 150 mg strength): advise patients to avoid direct exposure to excessive sunlight or UV light and consider sunscreens. CONTRACEPTION: patients and/or their partners should follow adequate contraception during, and for 130 days after, bicalutamide therapy. PAEDIATRIC: bicalutamide is contraindicated for use in children (§4.3), hence paedDose is null. MISSED DOSE (US labelling): take the next dose at the scheduled time; do not take the missed dose and do not double the next dose. SOURCE NOTE: the eMC §4.5 was not captured in this bundle (the §4.4 text is truncated at the source-fetch limit) — the interactions below are drawn from eMC §4.3 and §4.4 and from the US label §7, each marked with its provenance; review the full §4.5 in the SPC.