Intradermal delivery device including a needle assembly

Abstract

A drug delivery device including a needle assembly facilitates making intradermal injections using a variety of drug container types such as a syringe. A hub supports the needle while a limiter surrounds the needle. The limiter includes a skin engaging surface that is adapted to be received against the skin of an animal to be intradermally injected. A forward end of the needle extends beyond the skin engaging surface a selected distance to limit a depth that the needle penetrates into the animal's skin.

1 . A hypodermic needle assembly for use in making intradermal injections, comprising: 
 a hub portion that is able to be attached to a drug container;    a needle supported by the hub portion, the needle having a hollow body with a forward end extending away from the hub portion; and    a limiter portion that that is non-movable with respect to said hub portion and said limiter surrounds the needle and extends away from the hub portion toward the forward end of the needle, the limiter portion having a skin engaging surface that is adapted to be received against skin of an animal to receive an intradermal injection, the needle forward end extending beyond the skin engaging surface a selected distance such that the limiter portion limits an amount that the needle is able to penetrate through the skin of an animal.    
   
   
       2 . The assembly of  claim 1 , wherein the hub portion and the limiter portion are integrally formed as a single piece made from a plastic material.  
   
   
       3 . The assembly of  claim 1 , wherein the hub portion and the limiter portion are formed as separate pieces.  
   
   
       4 . The assembly of  claim 3 , wherein the limiter portion includes an inner cavity that receives at least a portion of the hub portion and the inner cavity includes an abutment surface that engages corresponding structure on the hub portion to thereby limit the amount that the needle forward end extends beyond the skin engaging surface.  
   
   
       5 . The assembly of  claim 3 , wherein the limiter portion is integrally formed as part of the syringe and the hub portion is received within the limiter portion.  
   
   
       6 . The assembly of  claim 5 , wherein the skin engaging surface surrounds the needle, and has a thickness defined between an inner diameter and an outer diameter and wherein the inner diameter is at least five times greater than an outside diameter of the needle.  
   
   
       7 . The assembly of  claim 6 , wherein the skin engaging surface is generally circular.  
   
   
       8 . The assembly of  claim 1 , wherein the skin engaging surface includes a central opening that is slightly larger than an outside dimension of the needle and the skin engaging surface is continuous.  
   
   
       9 . The assembly of  claim 1 , wherein the skin engaging surface is generally flat and defines a plane that is generally perpendicular to an axis of the needle and that is adapted to be received against skin of an animal to limit the penetration depth of the forward end of the needle and to maintain the needle in generally perpendicular orientation relative to the skin of the animal during the intradermal injection, the needle forward end extending beyond the skin engaging surface a preselected distance such that the penetration depth of the needle into the skin of the animal is limited to the dermis layer of the skin of the animal.  
   
   
       10 . The needle assembly of  claim 1 , wherein the selected distance that the forward end of the needle extends beyond the skin engaging surface is fixed.  
   
   
       11 . The assembly of  claim 1 , wherein the selected distance is in the range from approximately 0.5 mm to approximately 3 mm.  
   
   
       12 . The assembly of  claim 1 , wherein the skin engaging surface includes a contact surface area that is large enough to stabilize the assembly in a desired orientation relative to the skin.  
   
   
       13 . The assembly of  claim 12 , wherein the desired orientation is generally perpendicular to the skin.  
   
   
       14 . The assembly of  claim 1 , wherein the drug container is a syringe and the animal is human.  
   
   
       15 . An intradermal delivery device for use in making intradermal injections, comprising: 
 a drug container having a reservoir adapted to contain a selected substance and an outlet port that allows the substance to exit the reservoir during an injection, wherein said drug container comprises a syringe having a generally flat body portion that at least partially surrounds the reservoir, the body portion and the reservoir being made from two sheets of thermoplastic material such that side walls of the reservoir are selectively deflectable toward each other to expel a substance from the reservoir during an injection;    a needle in fluid communication with the outlet port, the needle having a forward end that is adapted to penetrate the skin of an animal; and    a limiter that is non-movable with respect to said hub portion and said limiter surrounds the needle and has a skin engaging surface that is adapted to be placed against the skin of the animal to receive an intradermal injection, the needle forward end extending away from the skin engaging surface a selected distance such that the limiter limits an amount that the needle forward end penetrates the skin, wherein said limiter is non-movable and limits penetration of the needle into the dermis layer of skin of the animal so that the substance is injected into the dermis layer of the animal.    
   
   
       16 . The device of  claim 15 , wherein the drug container is a syringe including a generally hollow, cylindrical body portion and a plunger that is received within the reservoir, the plunger being selectively movable within the reservoir to cause the substance to be forced out of the outlet port during an injection.  
   
   
       17 . The device of  claim 15 , including a hub portion that supports the needle and the hub portion is selectively secured to the drug container near the outlet port.  
   
   
       18 . The device of  claim 15 , wherein the drug container is a syringe includes a generally flat body portion that at least partially surrounds the reservoir, the body portion and the reservoir are made from two sheets of thermoplastic material such that side walls of the reservoir are selectively deflected toward each other to expel a substance from the reservoir during an injection.  
   
   
       19 . The device of  claim 18 , including a hub that supports the needle and is selectively secured to the syringe near the outlet port and a receiver adjacent the outlet port that is generally circular and the hub is completely received within the receiver and wherein the limiter is integrally formed with the receiver such that the limiter is permanently supported by the body portion adjacent the outlet port.  
   
   
       20 . The device of  claim 19 , wherein the skin engaging surface surrounds the needle, and has a thickness defined between an inner diameter and an outer diameter and wherein the inner diameter is at least five times greater than an outside diameter of the needle.  
   
   
       21 . The device of  claim 20 , wherein the skin engaging surface is generally circular.  
   
   
       22 . The device of  claim 19 , wherein the needle forward end extends away from the hub in a first direction and a needle back end extends away from the hub in a second direction, and including a sealing membrane that closes off the outlet port and wherein the needle back end pierces the sealing membrane when the hub is received by the receiver.  
   
   
       23 . The device of  claim 18 , including a hub that supports the needle and is selectively secured to the syringe near the outlet port and a receiver adjacent the outlet port that is generally circular and the hub is completely received within the receiver and wherein the limiter is formed separately from the receiver and is at least partially received by the receiver.  
   
   
       24 . The device of  claim 23 , wherein the limiter and the hub are integrally formed into a single piece structure.  
   
   
       25 . The device of  claim 15 , wherein the needle has a length and wherein the selected distance is much less than the needle length.  
   
   
       26 . The device of  claim 25 , wherein the selected distance is fixed and is in the range from approximately 0.5 mm to approximately 3 mm.  
   
   
       27 . The device of  claim 15 , wherein the skin engaging surface is generally flat and defines a plane that is generally perpendicular to an axis of the needle and that is adapted to be received against skin of an animal to limit the penetration depth of the forward end of the needle and to maintain the needle in generally perpendicular orientation relative to the skin of the animal during the intradermal injection, the needle forward end extending beyond the skin engaging surface a preselected distance such that the penetration depth of the needle into the skin of the animal is limited to the dermis layer of the skin of the animal.  
   
   
       28 . The device of  claim 15 , wherein the skin engaging surface includes a central opening that is slightly larger than an outside dimension of the needle and the skin engaging surface is continuous.  
   
   
       29 . The device of  claim 15 , wherein the skin engaging surface includes a contact surface area that is large enough to stabilize the assembly in a desired orientation relative to the skin.  
   
   
       30 . The device of  claim 15 , wherein the desired orientation is generally perpendicular to the skin.  
   
   
       31 . The device of  claim 15 , wherein the drug container is prefilled with a substance.  
   
   
       32 . A method of intradermally injecting at least one substance such as a drug, vaccine or the like into the skin, comprising the steps of: 
 pressing a needle perpendicularly to the skin, said needle in fluid communication with an outlet port of a drug container having a reservoir adapted to contain a selected substance and the outlet port providing an exit path for the substance from the reservoir during an intradermal injection;    injecting the substance into the skin with the depth of penetration of the needle being limited to the intradermal space of the skin by a non-movable limiter that surrounds the needle and has a skin engaging surface that is adapted to be placed against the skin and a forward end of the needle extending away from the skin engaging surface a selected distance such that the limiter limits penetration of the needle forward end to the dermis layer of the skin so that the substance is injected into the dermis layer of the skin, said step of injecting the substance comprising deflecting at least two sheets of thermoplastic material forming a generally flat body portion that at least partially surrounds the reservoir toward each other to expel the substance from the reservoir during an injection.    
   
   
       33 . The method of  claim 32 , wherein the step of pressing the needle perpendicularly to the skin of the animal includes orienting the needle perpendicularly to the skin.  
   
   
       34 . The method of  claim 32 , wherein the step of injecting the substance includes moving a plunger that is received within the reservoir, with the plunger being selectively movable within the reservoir to cause the substance to be forced out of the outlet port during the injection.  
   
   
       35 . The method of  claim 32 , wherein the step of injecting the substance into the skin of the animal includes deflecting at least two sheets of thermoplastic material forming a generally flat body portion that at least partially surrounds the reservoir toward each other to expel the substance from the reservoir during an injection.  
   
   
       36 . The method of  claim 32 , further comprising the step of filling the drug container with the substance to be intradermally injected.  
   
   
       37 . The method of  claim 32 , wherein said drug container is a syringe and said animal is human.