Mercilon (Organon) is a new combined oral contraceptive “developed with the mature pill user in mind”. Each tablet contains ethinyloestradiol 20µg + desogestrel 150µg. It is a lower dose version of Marvelon (ethinyloestradiol 30µg + desogestrel 150µg),1 which is intended for younger women, and like Marvelon contains the highly selective progestagen desogestrel, which is said to be more progestagenic and less androgenic than other commonly used progestagens.2 Like other monophasic combined oral contraceptives, Mercilon is taken daily for 21 days, followed by a 7-day break.