Method and device for painless injection of medication

Abstract

A method for providing a substantially painless injection of medication into a patient, including inserting an injection needle having an outside diameter greater than 0.20 mm and less than about 0.38 mm, and injecting a medicament through the needle and into the patient at a substantially constant volumetric flow rate of about 0.05 μL/s to about 50 μL/s that provides a painless injection. The method does not require the use of an anesthetic or that the medical personnel to spend a substantial amount of time performing the injection procedure, is relatively simple and inexpensive to perform and operate, and provides a relatively high degree of safety for both the medical personnel and for the patient.

1 . A method of injecting painlessly and intra-muscularly a liquid medicament to a patient, comprising the steps of:
 a) inserting an injection tip of an injection needle through the skin and into a muscle of a patient, the needle having an outside diameter greater than 0.20 mm and less than about 0.38 mm, and   b) injecting a liquid medicament through the needle and into the patient at a substantially constant volumetric flow rate of about 0.05 μL/s to about 50 μL/s.   
     
     
         2 . The method according to  claim 1  wherein the needle is selected from a 28 gauge, 30 gauge and a 32 gauge needle. 
     
     
         3 . The method according to  claim 1  wherein the volumetric flow rate is about 0.5 μL/s to about 20 μL/s. 
     
     
         4 . The method according to  claim 3  wherein the volumetric flow rate is about 1 μL/s to about 4 μL/s. 
     
     
         5 . The method according to  claim 1  wherein the step of inserting the needle further comprises inserting the injection tip to a pre-selected depth into the muscle. 
     
     
         6 . The method according to  claim 1  wherein the step of inserting further comprises inserting the needle normal to the surface of the patient's skin. 
     
     
         7 . The method according to  claim 1  further comprising the steps of providing a self-contained device that includes the injection needle, the liquid medicament, and a base that includes a means for semi-permanent attachment of the device to the skin of the patient, and attaching the device semi-permanently to the skin of the patient prior to the inserting step and during the injection step. 
     
     
         8 . The method according to  claim 7  further comprising the step of retracting the needle from the muscle and skin of the patient following completion of the injecting step. 
     
     
         9 . The method according to  claim 8  wherein the device can sequence automatically the inserting of the needle, the injecting of the medicament, and the retracting of the needle. 
     
     
         10 . The method according to  claim 7  wherein the volumetric flow rate is about 0.5 μL/s to about 20 μL/s. 
     
     
         11 . The method according to  claim 10  wherein the volumetric flow rate is about 1 μL/s to about 4 μL/s. 
     
     
         12 . A method of injecting a liquid medicament to a patient, comprising the steps of:
 providing a self-contained device that includes an injection needle, a liquid medicament, and a base;   attaching the device semi-permanently to the skin of a patient;   inserting an injection tip of the injection needle through the skin and into a muscle of the patient; and   injecting the liquid medicament through the needle and into the patient at a substantially constant volumetric flow rate of about 0.05 μL/s to about 50 μL/s.   
     
     
         13 . The method according to  claim 12 , wherein the needle has an outside diameter greater than 0.20 mm and less than about 0.38 mm. 
     
     
         14 . The method according to  claim 12 , wherein the step of inserting the needle further comprises inserting the injection tip to a pre-selected depth into the muscle. 
     
     
         15 . The method according to  claim 12 , further comprising the step of retracting the needle from the muscle and skin of the patient following completion of the injecting step. 
     
     
         16 . The method according to  claim 15 , wherein the device sequences automatically the inserting of the needle, the injecting of the medicament, and the retracting of the needle. 
     
     
         17 . A method of injecting a liquid medicament to a patient, comprising the steps of:
 providing a self-contained device that includes an injection needle, a liquid medicament, and a base;   attaching the device semi-permanently to the skin of a patient;   inserting an injection tip of the injection needle through the skin and into a muscle of the patient, the needle having an outside diameter great than 0.20 mm and less than about 0.38 mm; and   injecting the liquid medicament through the needle and into the patient at a substantially constant volumetric flow rate.   
     
     
         18 . The method according to  claim 17 , wherein the substantially constant volumetric flow rate is about 0.05 μL/s to about 50 μL/s. 
     
     
         19 . The method according to  claim 17 , wherein the step of inserting the needle further comprises inserting the injection tip to a pre-selected depth into the muscle. 
     
     
         20 . The method according to  claim 17 , further comprising the step of retracting the needle from the muscle and skin of the patient following completion of the injecting step.