I meant to say that azithromycin is safe and effective in nursing mothers, with no adverse effects for the child.
Dicloxacillin is a poor choice for any STD. It has no effect against chlamydia or the other bacteria that cause cervicitis in women and NGU in men, and borderline efficacy at best against gonorrhea and syphilis. The alternative to doxycycline is azithromycin 1.0 g orally in a single dose, which is safe and effective in pregnancy. If gonorrhea is a concern, then it's azithromycin plus a cephalosporin antibiotic, such cefixime or cefpodoxime; or a 2.0 g dose of azithromycin.
Regards-- HHH, MD