Patent ID: 8703739

Claim:
A bacteriostatic-heparin-containing catheter lock solution to be injected into an intravascular indwelling catheter, the solution comprising: a buffering agent selected from citrate, acetate, phthalate, succinate, and 3, 3-dimethyl-glutarate, and heparin or a salt thereof, wherein the buffering agent contains an organic or inorganic acid having an acid dissociation constant (pKa) of 3.0 to 6.5 at a concentration of 10 to 250 mM in the catheter lock solution, and the catheter lock solution has a pH of 3.0 to 4.97 and an osmotic pressure ratio of 0.5 to 3.0, wherein a preservative, an antimicrobial agent, or an antibiotic is not added to the catheter lock solution.