Digestive Enzymes vs. Systemic Enzymes 
Digestive enzymes conduct their actions in the stomach to digest food while systemic enzymes are enterically coated to prevent contact with the stomach acid. This way they pass through the stomach into the intestines where they are absorbed by the body. 

The primary function of systemic enzymes 
Systemic enzymes fight inflammation, fibrosis (scar tissue), and viruses; modulate the immune system; and cleanse the blood. 
 

Systemic Enzyme Ingredients 

Proteolytic Enzyme (Protease) 
The term "proteolytic" refers to all enzymes that digest protein. Other classes of enzymes include Amylase, a digestive enzyme that breaks down carbohydrates, and Lipase, a digestive enzyme that breaks down fat during the digestive process. Each of these help in the digestion of food, which in turn helps with absorption of those essential nutrients in the diet. In the body, proteolytic digestive enzymes are produced in the pancreas, but supplemental forms of enzymes may come from fngal or bacterial sources, extraction from the pancreas of livestock animals (trypsin/chymotrypsin) or extraction from plants (such as papain from the papaya and Bromelain from pineapples). The primary uses of proteolytic enzymes in dietary supplements are used as digestive enzymes, anti-inflammatory agents, and pain relievers. 
  
There are a number of clinical trials showing the benefit of using oral proteolytic enzymes as a digestive aid. Proteolytic enzymes are also theorized to help reduce symptoms of food allergies, and as a treatment for rheumatoid arthritis and other autoimmune diseases. 

Perhaps the strongest evidence for benefits of proteolytic enzyme supplements come from numerous European studies showing various enzyme blends to be effective in accelerating recovery from exercise and injury in sportsmen as well as tissue repain in patients following surgery. In one study of footballers suffering from ankle injuries, proteolytic enzyme supplements accerlerated healing and got players back on the field about 50% faster than athletes assigned to receive a placebo tablet. 1 A handful of other small trials in athletes have shown enzymes can help reduce inflammation, speed healing of bruises and other tissue injuries (including fractures), and reduce overall recovery time when compared to athletes taking a placebo. 2-3 In patients recovering from facial and various reconstructive sugeries, treatment with proteolytic enzymes significantly reduced swelling, bruising and stiffness compared to placebo groups. 9-11 

Serrapeptase 
Serrapeptase, also known as Serratia peptidase, is a proteolytic enzyme isolated from the non-pathogenic enterobacteria Serratia E15. The enzyme is found naturally in the intestine of the silkworm, which is used by the silkworm to dissolve the cocoon and emerge as a moth. When consumed in unprotected tablets or capsules, the enzyme is destroyed by acid in the stomach. However, when enterically coated, the enzyme is destroyed by acid in the stomach. However, when enterically coated, the enzyme passes through the stomach unchanged and can be absorbed by the intestine. 

It has many clinical uses, including as an anti-inflammatory agent (particularly for post traumatic swelling), for fibrocystic breast disease, and for bronchitis (serrapeptase loosens and expels mucous). 

Serrapeptase digests dead tissue, blood clots, cysts, and arterial plaque. The late German physician Dr. Hans Nieper used serrapeptase to treat arterial blockage in his coronary patients. Clinical studies show that serrapeptase induces fibrinolytic, anti-inflammatory and anti-edemic (prevents swelling and fluid retention) activity in a number of tissues, and that its anti-inflammatory effects are superior to other proteolytic enzymes. 12 Besides reducing inflammation, one of serrapeptase's most profound benefits is reduction of pain, due to its ability to block the release of pain-inducing amines from inflamed tissues. 13 Physicians throughout Europe and Asia have recognized the anti-inflammatory and pain-blocking benefits of this naturally occurring substance, and are using it in treatment as an alternative to salicylates, ibuprofen, and other NSAIDS. 14 

Bromelain and Papain 
Both Bromelain and Papain are plant-derived proteolytic enzymes. Bromelain, also known as bromelin, is a protein-digesting enzyme extracted from the flesh and stem of the pineapple plant, Ananas Comosus. Papain is a proteolytic enzyme isolated fromthe papaya plant, Carica Papaya. Bromelain is most notable for its effectiveness in the reduction of inflammation and decreasing swelling, but the scope of its benefits continues to increase. As a natural anti-inflammatory enzyme, bromelain has many uses. Arthritis patients may reduce the swelling that causes joint pain by taking bromelain. Bromelain may also be helpful for the pain, numbness, tingling, aching and loss of motor and sensory function in the fingers resulting from carpal tunnel syndrome (CTS). 15, 16 Prevention of the adhesiveness of platelets to endothelial cell walls was accomplished with 0.1 mcg/ml of Bromelain. 16a Thus the benefti of bromelain occurs over a broad range of doses, and even small amounts may be beneficial to anyone at risk to thrombotic heart attack or stroke. Papain has been shown to be effective in preventing burn wound infection and helping remove dead cells. 17 

Papain is also used for defibrinating wounds in hopitals, preventing cornea scar deformation, treating jellyfish and insect stings, treating edemas and inflammatory processes, accelerating wound healing, for indigestion, dissolving membranes in diphtheria, treating ulcers, and to reduce fever, swelling and adhesions after surgery. 

Amla 
Also known as Indian gooseberry (Emblica officinalis) is the richest source of Vitamin C. The Vitamin C in Amla is from the Rutin family, and there is about 50 mg per System Enzyme capsule. It also contains tannic acid, glucose, protein, cellulose and Calcium. Amla is useful for stomach problems, it is antipyretic, hair tonic and nerve brain tonic. It is also useful in anemia, hyperacidity and in gynecological problems and epistaxis. Amla is considered to have restorative and preventative properties. 

Rutin 
Rutin is one of the many existing Flavonoids, which are a class of water-soluble plant pigments. Flavonoids support health by strengthening capillaries and other connective tissue, and some function as anti-inflammatory, antihistaminic, and antiviral agents. Rutin and several other flavonoids may also protect blood vessels. Rutin was shown to stimulate wound healing in rats and augment the tensile strength of scar tissue significantly. 18 

To learn about "activation dose" for enzymes, click HERE. 

References 
1) Buck JE, Phillips N. Trial of Chymoral in professional footballers. Br J Clin Pract. 1970 Sep;24(9):375-7 

2) Craig RP. The quantitative evaluation of the use of oral proteolytic enzymes in the treatment of sprained ankles. Injury. 1975 May;6(4):313-6 

3) Fisher JD, Weeks RL, Curry WM, Hrinda ME, Rosen LL. Effects of an oral enzyme preparation, Chymoral, upon serum proteins associated with injury (acute phase reactants) in man. J Med. 1974;5(5):258-73 
4) France LH. Treatment of injuries with orally administered Varidase as compared to Chymoral and Tanderil. Praxis. 1968 May 14;57(19):683-5 

5) Gal P, Ted F, Skotakova J, Mach V. Systemic enzyme therapy in the treatment of supracondylar fractures of the humerus in children. Rozhi Chir. 1998 Dec;77912):574-6 

6) Hingorani K. Oral enzyme therapy in severe back pain. Br J Clin Pract. 1968 May 5;22(5):209-10 

7) Rathgeber WF. The use of proteolytic enzymes (chymoral ) in sporting injuries. S Afr Med J. 1971 Feb 13;45(7):181-3 

8) Schwinger O. Results of oral enzyme therapy in wounds of muscles, tendons and bones after accidents. Wien Med Wochenschr. 1970 Sep 5;120(36):603-5 

9) Duskova M, Wald M. Orally administered proteases in aesthetic surgery. Aesthetic Plat Surg. 1999 Jan-Feb;23(1):41-4 

10) Hoemecke R, Doenicke A. Perioperative enzyme theapy. A significant supplement to postoperative pain therapy? Anaesthesist. 1993 Dec;42(12):856-61 

11) Lie KK, Larsen RD, Posch JL. Therapeutic value of oral proteolytic enzymes following hand surgery. Arch Surg. 1969 Jan;98(1):103-4 

12) Mazzone A, Catalani M, Constanzo M, Drusian A, Mandoli A, Russo S, Guarini E, Vesperini G. Evaluation of Serratia peptidase in acute or chronic inflammation of otorhinolaryngolog pathology: a multicentre, double-blind, randomized trial versus placebo. J Int Med Res 1990,18(5):379-88 

13) Mazzone A, et al. Evaluation of Serratia peptidase in acute or chronic inflammation of otorhinolaryngolog pathology: a multicentre, double-blind, randomized trial versus placebo. J Int Med Res 1990,18(5):379-88 

14) Aso T, et al. Breast engorgement and its treatment: Clinical effects of Danzen, an anti-inflammatory enzyme preparation. The world of Obstetrics and Gynecology (Japanese). 1981;33:371-9 

15) Petry, Judy J. "Nutritional supplements and surgical patients" AORN Journal (June 1997) 

16) Kelly, G.S. "Bromelain: A Literature Review and Discussion of Its Therapeutic Applications." Alternative Medicine Review (November 1, 1996). 

16a) Metzig, C et al Bromelain Proteases reduce human platelet aggregation in vitro, adhesion to bovine endothelial cells and thrombus formation in rat vessels in vivo. In Vivo 13(1):7-12 Jan-Feb 1999 

17) Starley, I.F.; Mohammed, P.; Schneider, G.; Bickler, SW. The treatment of peadiatric burns using topical papaya. Burns 1999 Nov 25(7)636-9 

18) Wilhelmi, G. Effect of O-(beta-hydroxyelthyl)-rutiside on wound healing in the rat. J Pharmacology 1979;19(2):82-5