The two methods of administering antibiotics in the tactical setting are by mouth or by parenteral (intramuscular, intravenous, or intraosseous) injection.

The logistical issues associated with carrying, reconstituting, and then injecting or infusing parenteral medications make use of oral antibiotics the preferred route, when oral administration is possible.

Parenteral administration of antibiotics is required in casualties who are unconscious or who cannot take medications by mouth (for example, due to maxillofacial injuries). It is also required for casualties in shock, in whom the gastrointestinal tract blood flow may be inadequate for absorption of oral medications.

Prophylactic antibiotic therapy should be accompanied by wound irrigation, surgical debridement of the wound when the situation permits, immunization for tetanus, and appropriate post-surgical care of the wound in order to minimize the risk of wound infection.