Catheter lock solution formulations
A liquid excipient is added to a lock solution formulation containing a lower alcohol and an anti-coagulant, antibiotic, and/or anti-microbial, such as the ethanol and tri-sodium citrate lock solution formulation, to prevent citrate from crystallizing in catheters made from silicone. The locking solution could include a liquid excipient, such as glycerol, polysorbate-20, or polyethylene glycol (PEG)-400, along with a lower alcohol, such as ethanol, and an anti-coagulant, such as tri-sodium citrate, antibiotic, and/or anti-microbial.
1. A catheter locking method comprising: introducing a locking composition into a lumen of the implantable catheter, wherein the locking composition comprises:
a lower alcohol comprising ethanol;
sodium citrate; and
a liquid excipient comprising one or more of glycerol and polysorbate-20, wherein the liquid excipient is present in an amount less than the amount of sodium citrate and at a sufficient concentration to inhibit crystallization of sodium citrate.
2. The method of claim 1 , wherein the excipient is selected from:
a. glycerol present in the amount of about 1% by weight of the locking composition and polysorbate-20 present in the amount of about 0.5% by weight of the locking composition;
b. glycerol present in the amount of about 0.75% by weight of the locking composition and polysorbate-20 present in the amount of about 0.75% by weight of the locking composition; and
c. glycerol present in the amount of about 0.5% by weight of the locking composition and polysorbate-20 present in the amount of about 0.5% by weight of the locking composition.
3. The method of claim 1 wherein the lower alcohol is ethanol and the excipient comprises polysorbate-20 and glycerol.
4. The method of claim 3 wherein polysorbate-20 comprises at least 0.5% by weight and glycerol comprises at least 1.5% by weight of the locking composition.
5. The method of claim 1 , the locking composition further comprising an antimicrobial compound selected from the group consisting of taurolidine, triclosan, chlorhexidine, gentamicin, vancomycin, and combinations thereof.
6. The method of claim 1 , the excipient being present in an amount of at least 0.5% by weight of the locking composition.
7. The method of claim 1 , the excipient being present in an amount ranging from 0.5-2% by weight of the locking composition.
8. The method of claim 1 , the excipient being present in an amount of up to 2% by weight of the locking composition.
9. The method of claim 1 , the excipient being a combination of at least two excipients present in an amount of up to 2% by weight of the locking composition.
10. The method of claim 1 , the locking composition comprising at least about 1% by weight of the excipient.
11. The method of claim 10 , the locking composition comprising at least about 2% by weight of the excipient.
12. The method of claim 11 , the locking composition comprising at least about 4% sodium citrate and at least about 30% of ethanol.