Drug delivery system for accelerated subcutaneous absorption

Abstract

A method for accelerating subcutaneous absorption of a fluid or drug into the systemic circulation of a specific targeted tissue. A first drug operative to produce local capillary vasodilatation and/or increase the rate of bulk flow of solution through the interstitial space is mixed with a fluid. The fluid may contain a crystalloid solution or a dilute solution of a pharmacologic drug required for a routine or emergency therapeutic treatment for a patient. The first drug is substantially non-toxic to the patient. The fluid mixed with the first drug is then delivered subcutaneously or into deeper tissues of the patient, by use of a hyperdermic needle or infiltration cannula. As the capillaries are dilated, the fluid is efficiently absorbed and circulated systemically.

1 . A drug delivery method, comprising:
 a) dissolving a first drug at a substantially non-toxic concentration with a fluid solvent, wherein the first drug is operative to produce local capillary vasodilatation or to produce increased bulk flow of fluid by depolymerization of hyaluronic acid; and   b) subcutaneously or intramuscularly applying the fluid containing the first drug to a patient.   
     
     
         2 . The method of  claim 1 , wherein the first drug includes methyl-nicotinamide, methyl-nicotinate or hyaluronidase. 
     
     
         3 . The treatment of  claim 1 , wherein fluid includes physiologic saline. 
     
     
         4 . The treatment of  claim 1 , wherein the fluid includes a dilute solution of local anesthetic. 
     
     
         5 . The treatment of  claim 1 , wherein the fluid includes a dilute solution of lidocaine. 
     
     
         6 . The treatment of  claim 1 , wherein step (b) includes applying the fluid containing the first drug by subcutaneous infiltration. 
     
     
         7 . The method of  claim 6 , wherein step (b) includes:
 b1) inserting an infiltration cannula under skin of the patient; and   b2) infiltrating the fluid containing the first drug into subcutaneous tissue or muscle of the patient through the infiltration cannula.   
     
     
         8 . The method of  claim 7 , wherein step (b1) includes inserting a plastic infiltrator under the skin of the patient. 
     
     
         9 . The method of  claim 1 , further comprising the step of:
 c) applying a solution of a vasoconstrictive drug operative to cause vasoconstriction of cutaneous blood vessels of the patient.   
     
     
         10 . The method of  claim 9 , wherein the vasoconstrictive drug includes a solution of epinephrine. 
     
     
         11 . The method of  claim 1 , wherein the fluid contains a second drug for treating a subcutaneous tissue of the patient 
     
     
         12 . A method of increasing absorption rate of a therapeutic drug, comprising:
 applying a first solution in a first level under skin of a patient, wherein the first solution contains a therapeutic drug for treating subcutaneous tissue of the patient; and   applying a second solution in a second level under the skin of the patient, wherein the second solution contains a vasoconstrictive drug; wherein   the second level is deeper than the first level to serve as a buffer for preventing or delaying absorption of the therapeutic drug into deep vascular tissue.   
     
     
         13 . The method of  claim 12 , wherein the first solution further contains a vasodilation drug. 
     
     
         14 . The method of  claim 12 , wherein the vasoconstrictive drug includes epinephrine. 
     
     
         15 . The method of  claim 12 , wherein the first level includes a deep plane of the subcutaneous tissue, and the second level includes a superficial plane immediately below dermis of the patient. 
     
     
         16 . A method of increasing absorption rate of a therapeutic drug, comprising:
 applying a first solution in a first level under the skin of a patient, wherein the first solution contains a therapeutic drug for treating the skin of the patient; and   applying a second solution in a second level under the skin of the patient, wherein the second solution contains a vasoconstrictive drug only; wherein   the first level is deeper than the second level to serve as a buffer for preventing or delaying absorption of the therapeutic drug into superficial region of the skin.   
     
     
         17 . The method of  claim 16 , wherein the first solution further contains a vasodilation drug. 
     
     
         18 . The method of  claim 17 , wherein the vasoconstrictive drug comprises epinephrine.