Chromic gut absorbable sterile surgical sutures are composed of purified connective tissue (mostly collagen) derived from the serosal layer of beef (bovine) intestines. They are packaged in a solution of 89% isopropanol, 10% water and 1% triethanolmaine. Chromic gut sutures are treated with chromic salt solution. Chromic gut sutures are indicated for use in general soft tissue approximation and/or ligation, including use in ophthalmic surgery, but not in cardiovascular or neurological surgery.