Ceftriaxone plus Amoxicillin (Amoxil®, Polymox®, Trimox®)

STI Standards

Midwives may independently prescribe, order, and administer drugs in the community, hospital or other sites of midwifery practice to treat sexually transmitted infections for clients in case, as designated under specialized practice certification. Midwives without specialized practice certification in sexually transmitted infections management are required to refer their clients to an appropriate health care practitioner for treatment. 

Ceftriaxone is an oral third generation broad spectrum semisynthetic cephalosporin antibiotic. Amoxicillin (refer to the Chlamydia Trachomatis section). See dosage below for treatment of Neisseira Gonorrhea.

Indications and Clinical Use:

Used for the treatment of asymptomatic or symptomatic Neisseira Gonorrhea in pregnancy and the postpartum in combination with Amoxicillin.


Allergy to cephalosporin group of antibiotics.

Warnings and Precautions:

Chance of cross-reactivity is low (around 3%) if the patient is Penicillin sensitive, however do not use it for highly allergic (e.g., anaphylactic) patients. Use with caution in clients with colitis.

Alteration of GI flora may occur, as with all antibiotics, see Probiotic Use with Antibiotics.


Compatible – Use during 1st trimester may be associated with cardiovascular defects.


Limited Data – compatible.

Adverse Reactions:

Adult – Diarrhea, allergic rash, thrush and/or colitis.
Breastfed infant – monitor for vomiting, diarrhea, rash and changes in gastrointestinal flora.

Dosage and Administration:

Neisseria Gonorrhea:
Ceftriaxone: 250 mg IM as a single dose plus
Amoxicillin: 500 mg orally every 8 hours (tid) for 7 days. (see write up on Amoxicillin in the Chlamydia Trachomatis section).

Onset of Action:

Time to peak, serum: 1 hour.

Duration of Action:

Half-life elimination: 7.3 hours.