The results of an in vivo evaluation of silver sulfadiazine dry foam are described. Using burned guinea pigs infected with Pseudomonas aeruginosa, silver sulfadiazine was applied every 12hr as the dry foam or ointment. After 72 hr of therapy with the medicated dry foam, only one of the 15 burns remained infected while seven of the 15 burns remained positive for Pseudomonas after treatment with the corresponding medicated ointment (p less than 0.05 greater than 0.01). It is suggested that the medicated dry foam provided significantly greater activity in treating a supraeschar burn wound infection of recent onset. In addition, a modified crossover study demonstrated that both the medicated dry foam and ointment are less effective in treating subeschar burn wound infections.