Summary of the evidence

This is a summary of the evidence, for full details see the evidence review.

The evidence included 1 systematic review (Medeiros et al. 2001) and 2 randomised controlled trials (Quinn et al. 2010, Broder et al. 2004). These studies considered various prophylactic antibiotics compared with no antibiotic or placebo for managing animal and human bites. No evidence was identified for choice of antibiotic, course length or route of administration.

Antibiotic efficacy

If no route of administration for an antibiotic is given in the evidence review, no details were reported in the primary study.

For human bites

Prophylactic antibiotics (oral cefaclor, intravenous cefazolin, intravenous benzylpenicillin, and oral cefalexin or penicillin) were shown to be more effective than placebo at reducing signs of infection after human bites in adults.

For animal bites

There was no difference between prophylactic antibiotics (oral phenoxymethylpenicillin, oral dicloxacillin, oxacillin, oral cefalexin, oral erythromycin, co‑trimoxazole, cloxacillin and oral co‑amoxiclav) and no treatment or placebo in signs of infection after dog bites in adults, young people and children.

One small study suggests that there was no difference between a prophylactic antibiotic (oxacillin) and placebo in signs of infection after cat bites in adults.

By bite type

There was no difference between prophylactic antibiotics (oxacillin, oral phenoxymethylpenicillin, oral dicloxacillin, oral cefalexin and oral erythromycin) and no treatment or placebo in the incidence of infection in adults, young people and children when treating puncture, laceration or avulsion wounds.

By bite location

There was no difference between prophylactic antibiotics (oral dicloxacillin, oral cefalexin, oral erythromycin, oral phenoxymethylpenicillin, co‑trimoxazole, oral cefaclor, intravenous cefazolin and intravenous penicillin) and no treatment or placebo in the incidence of infection in adults, young people and children when treating trunk, head and neck, hand or arm wounds.

Choice of antibiotic

There was no evidence identified about the choice of antibiotic.

Course length

There was no evidence identified about the course length of antibiotics.

Route of administration

There was no evidence identified about the route of administration of antibiotics.

  • National Institute for Health and Care Excellence (NICE)