Retardation of wound healing by procaine.

Lignocaine has previously been shown to retard wound healing; the retardation is directly related to the concentration of the drug used and is enhanced by the addition of adrenaline. The study described in this paper aimed to determine whether procaine has a similar effect and, if so, whether the effect of sterile water alone and of procaine in various concentrations on the tensile strength of skin wounds in rats. 5 and 7 days after operation. At 5 days sterile water had produced a significant retardation of wound healing. All concentrations of procaine produced significant retardation of healing at 5 days and adrenaline enhanced this effect. By 7 days the effect was greatly diminished and only those rats injected with 2 per cent procaine with adrenaline had significantly weaker wounds. The study suggests that 2 per cent procaine with adrenaline is better avoided and even when lower concentrations are used sutures should be retained for 7 days.