Two-dose syringe

A syringe for delivering two separated bodies of fluid into the urethra, said syringe comprising:

• a first piston made of a compressible, resilient material for separating said two bodies of fluid;
• a second piston for pushing said two bodies of fluid out of said syringe;
• and
• a walled fluid chamber having a no-pass zone in which said pistons can slide and which has a cross section shaped so that each of said pistons conforms to its wall, preventing the passing of fluid around said pistons when they are in said no-pass zone;
• a nozzle to direct fluid pushed out of said syringe by said pistons, which nozzle has a tip with an external shape and size to fit into a urethra;
• and a bypass zone, for receiving said first piston, which connects said no-pass and output zones and which has at least one ridge projecting into said fluid chamber from its wall to push a portion of said first piston away from said wall when said first piston enters said bypass zone so that the fluid between said first and second pistons can pass around said first piston to said output zone.

A syringe for delivering two separated bodies of fluid into the urethra, said syringe comprising:

• a first piston for separating said two bodies of fluid;
• a second piston for pushing said two bodies of fluid out of said syringe;
• a fluid chamber having a no-pass zone in which said pistons can slide and which has a cross section that each of said pistons substantially fills, preventing the flow of fluid around said pistons when they are in said no-pass zone;
• a nozzle to direct fluid pushed out of said syringe by said pistons, which nozzle has a tip with an external shape and size to fit into, and make a seal with, a urethra;
• and a bypass zone, for receiving said first piston, which connects said no-pass zone and said nozzle and which has a cross section that said first piston is unable to fill, so that, when said first piston enters said bypass zone, the fluid between said first and second pistons can pass around said first piston to said nozzle;
• a removable nozzle blocking means for preventing fluid from exiting said nozzle until said blocking means is removed;
• a first body of fluid between said blocking means and said first piston;
• a second body of fluid between said first and second pistons;
• wherein said first piston is made of a compressible, resilient material, said fluid chamber has a wall and said bypass zone has at least one ridge projecting into said fluid chamber from its wall to push a portion of said first piston away from said wall when said first piston enters said bypass zone so that the fluid between said first and second pistons can pass around said first piston to said nozzle;
• and
• wherein one of said bodies of fluid is an antiseptic lubricant and the other is an anesthetic lubricant.

A two dose syringe comprising:

• an integral fluid chamber having an open end, a partially closed end, and a bypass zone located axially between said open end and said partially closed end, said bypass zone containing one or more ridges on the inside wall of said fluid chamber reducing the cross-sectional area of said chamber in the bypass zone;
• a first piston made of a compressible, resilient material, disposed in said fluid chamber to create a sliding, fluid-tight seal with the inner wall of said chamber, thus sealing the open end of the chamber;
• and
• a second piston located axially between said bypass zone and said first piston to divide said chamber into two sections, and not structurally connected with said first piston, said second piston being formed of a compressible, resilient material and forming a sliding, fluid-tight seal with the inner wall of said chamber.

A pre-filled two dose syringe comprising:

• an integral fluid chamber having an open end, a partially closed end, and a bypass zone located axially between said open end and said partially closed end, said bypass zone containing one or more ridges of the inside wall of said fluid chamber reducing the cross-sectional area of said chamber in the bypass zone;
• a first piston made of a compressible, resilient material, disposed in said fluid chamber to create a sliding, fluid-tight seal with the inner wall of said chamber, thus sealing the open end of the chamber;
• and
• a second piston located axially between said bypass zone and said first piston to divide said chamber into two sections, and not structurally connected with said first piston, said second piston being formed of a compressible, resilient material and forming a sliding, fluid-tight seal with the inner wall of said chamber;
• a removable cap sealably covering said partially open end to prevent leakage;
• a first fluid substance located between said cap and said second piston;
• and
• a second fluid substance located between said first and second pistons.

A method for preparing a urethra for catheterization comprising injecting an antiseptic lubricant and an anesthetic lubricant into said urethra using a prefilled syringe;

• said prefilled syringe comprising an integral fluid chamber having an open end, a partially closed end, and a bypass zone located axially between said open end and said partially closed end, said bypass zone containing one or more ridges on the inside wall of said fluid chamber reducing the cross-sectional area of said chamber in the bypass zone;
• a first piston made of a compressible, resilient material, disposed in said fluid chamber to create a sliding, fluid-tight seal with the inner wall of said chamber, thus sealing the open end of the chamber;
• and
• a second piston located axially between said bypass zone and said first piston to divide said chamber into two sections, and not structurally connected with said first piston, said second piston being formed of a compressible, resilient material and forming a sliding, fluid-tight seal with the inner wall of said chamber;
• a removable cap sealably covering said partially open end to prevent leakage;
• a first fluid substance located between said cap and said second piston and;
• a second fluid substance located between said first and second pistons;
• wherein said first piston is moved forward part way in said syringe by pressing a plunger, thereby dispensing said first fluid substance into said urethra and moving said second piston into the bypass zone;
• and
• wherein said first piston is further moved completely forward in said syringe by pressing said plunger as far as it will go, thereby dispensing said second fluid substance into the urethra.