The invention relates to the use of specific tripeptides for the treatment of postlesional diseases of ischemic, traumatic or toxic origin. The tripeptide derivatives satisfy formula (I), wherein X represents OH, (C.sub.1-5)alkoxy, NH.sub.2, NH--C.sub.1-5-alkyl, N(C.sub.1-5 alkyl).sub.2; R.sub.1 is a residue derived from any of the amino acids Phe, Tyr, Trp, Pro, each of which may optionally be substituted by a (C.sub.1-5) alkoxy group, a (C.sub.1-5) alkyl group or a halogen atom, and Ala, Val, Leu, or Ile; R.sub.2 is a residue which is derived from any of the amino acids Gly, Ala, Ile, Val, Ser, Thr, His, Arg, Lys, Pro, Glu, Gln, pGlu, Asp, Leu and Asn; R.sub.3 and R.sub.4 independently represent H, OH, (C1 C5) alkyl, or (C.sub.1-5)alkoxy, provided that R.sub.3 and R.sub.4 are not both OH or (C.sub.1-5)alkoxy; R.sub.5 represents H, OH, (C.sub.1-5)alkyl or (C.sub.1-5)alkoxy; and wherein R.sub.0 preferably represents a cinnamoyl residue; or pharmaceutically acceptable salts thereof.