Systemic antibiotics are routinely used to treat infection in wounds such as lacerations and abrasions. Kraus and colleagues evaluated the efficacy of oral cephalexin and topical mupirocin cream in the treatment of such wounds. Mupirocin cream is a relatively new formulation of mupirocin and is often preferred over the ointment form because the cream may be used on wounds that should be kept dry.

The randomized double-blind trial was conducted at 53 locations in the United States. The 706 patients in the study had infections of lacerations (up to 10 cm [4 in] in length), abrasions (up to 100 cm² [15.5 in²] in area), scratches, biopsy sites or body-piercing sites. Excluded were patients who had infections, such as cellulitis, abscess and bite wounds, that would not ordinarily be treated with a topical antibiotic.

A total of 349 patients received oral cephalexin, and 357 received mupirocin cream; 478 were considered evaluable at the end of the study. Oral cephalexin was administered in a dosage of 250 mg four times daily; patients weighing less than 40 kg (88 lb) received a dosage of 25 mg per kg per day in four divided doses. Mupirocin cream (2 percent) was applied three times daily. Each patient also received the placebo form of the other medication (i.e., placebo capsules if mupirocin cream was used or placebo cream if oral cephalexin was used).

A Wright stain (to check for white blood cells from the wound exudate) was performed two days before treatment was instituted. The wounds were examined after three to five days of therapy and again two to three days after completion of treatment. A final bacteriologic evaluation was performed seven to 12 days after completion of the medication. Clinical response was defined as “complete resolution” or “sustained improvement” without the need for further treatment. “Clinical recurrence” was judged to have occurred in patients who required additional antibiotic. Response to treatment was classified as “unable to determine” if a valid evaluation could not be completed. Adverse reactions were recorded.

Treatment was successful in 95 percent of the patients in both groups. Treatment failure occurred in 12 of the 245 patients in the mupirocin group (4.9 percent) and in 11 of the 233 patients in the cephalexin group (4.7 percent). Similar microorganisms were recovered in each group; the bacteriologic success rate was 97 percent in the mupirocin group and 99 percent in the cephalexin group. The incidence of adverse events did not differ statistically in the two groups: 7.6 percent in the mupirocin group and 9.5 percent in the cephalexin group.

The authors conclude that mupirocin cream is as effective, safe and tolerable as oral cephalexin in the treatment of minor secondarily infected wounds.