A pharmaceutical composition for topical administration comprising an analgesic effective amount of a peptide comprising L-amino acids of the formula (I): pGLU-X--Y-Z M (I) and a pharmaceutically acceptable excipient. X is an amino acid selected from the group consisting of GLY, VAL, GLU, ASP, SER, ALA, ASN, GLN, ILE, LEU, PRO, LYS and ARG, Y is TRP or THR, and Z is any L-amino acid, or Z is null. When Z is any L-amino acid, one but not both of Y and Z is TRP, and when Z is null, Y=TRP. An alkyl group may be attached to an amino acid of the peptide. Also disclosed are the peptide, the preparation of the pharmaceutical composition and a topical method of treating or preventing pain in a mammal.