Bromelain

What does it do? Bromelain is one of a group of proteolytic enzymes (enzymes capable of digesting protein). It is widely believed that most orally ingested enzymes are destroyed by the digestive juices prior to being absorbed. However, there is evidence that significant amounts of bromelain can be absorbed intact.1 Proteolytic enzymes other than bromelain are often used with people who suffer from malabsorption. Although bromelain in combination with other enzymes and ox bile has been reported to help digest food,2 it is generally not used for this purpose. However, bromelain does contribute to the digestion of protein, and may therefore be used as a digestive aid. Although many doctors assume that other proteolytic enzymes, such as those found in pancreatin, are more effective than bromelain in helping digestion and absorption, almost no research compares the relative effects of these enzymes.

Bromelain is an anti-inflammatory agent and for this reason is helpful in healing minor injuries, particularly sprains and strains, muscle injuries, and the pain, swelling, and tenderness that accompany sports injuries.3 4 5 Topically applied bromelain in the form of a cream may be beneficial for cleaning debris from burns 6 and frostbite,7 possibly enhancing the rate of healing.8 This use of bromelain should be supervised by a doctor.

Also as a result of its anti-inflammatory effect, bromelain has been found to dramatically reduce postoperative swelling in controlled human research.9 Double-blind research has found bromelain effective in reducing swelling, bruising,10 and pain, for women having minor surgery in conjunction with giving birth (episiotomy).11

The anti-inflammatory effect of bromelain is the probable reason this enzyme has been found effective for people suffering from sinusitis.12 Some of the evidence supporting bromelain in the treatment of sinusitis comes from double-blind research.13

Bromelain, in combination with trypsin (another enzyme) may enhance the effect of antibiotics in people with a urinary tract infection. In a double-blind study, 100% of people who received bromelain/trypsin in combination with antibiotics had a resolution of their infection, compared to only 46% of those who received antibiotics alone.14

Again, probably due to its anti-inflammatory action, bromelain was reported to help patients with rheumatoid arthritis in preliminary research.15 In that trial, in which bromelain was given for varying (3-week to 13-month) periods, 73% had good to excellent results.

Bromelain is a natural blood thinner because it prevents excessive blood platelet stickiness.16 This may explain, in part, the positive reports in a few clinical trials of bromelain to decrease symptoms of angina and thrombophlebitis.17 18 In addition, bromelain reduces the thickness of mucus, which may benefit patients with asthma or chronic bronchitis.19

Preliminary evidence in both animals and people suggests that bromelain may possess antitumor activity, though the true importance of this effect is poorly understood.20

Bromelain can induce beneficial changes in white blood cells with possible effects on immune function.21 22 However, whether these effects would help people with immune system problems remains unclear.

Where is it found? Bromelain is found mostly in the stems of pineapples and is available as a dietary supplement.

Bromelain has been used in connection with the following conditions (refer to the individual health concern for complete information):

Rating Health Concerns
3Stars Sinusitis
Wound healing
2Stars Post-surgical healing
Prostatitis (NBP, PD)
Sprains and strains
Tendinitis
Urinary tract infection
1Star Angina
Asthma
Low back pain
Rheumatoid arthritis
Thrombophlebitis
3Stars Reliable and relatively consistent scientific data showing a substantial health benefit.
2Stars Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
1Star An herb is primarily supported by traditional use, or the herb or supplement has little scientific support and/or minimal health benefit.

Who is likely to be deficient? Since bromelain is not essential, deficiencies of this plant-based enzyme do not exist.

How much is usually taken? Assessing the right amount of bromelain to take is complicated. Most bromelain research was conducted years ago, when amounts used were listed in units of activity that no longer exist. These old units do not precisely convert to new ones. Today, bromelain is measured in MCUs (milk clotting units) or GDUs (gelatin dissolving units). One GDU equals approximately 1.5 MCU. Strong products contain at least 2,000 MCU (1,200–1,333 GDU) per gram (1,000 mg). A supplement containing 500 mg labeled “2,000 MCU per gram” would have 1,000 MCU of activity. Some doctors recommend as much as 3,000 MCU taken three times per day for several days, followed by 2,000 MCU three times per day.23 Much of the research uses smaller amounts, more like the equivalent of approximately 500 MCU taken four times per day. However, most of the bromelain used in the studies was enteric-coated in order to prevent it from being destroyed by gastric juice. It is likely, therefore, that currently available bromelain preparations (which typically are not enteric-coated) are of lower potency than the bromelain used in most studies.

Are there any side effects or interactions? Bromelain is generally safe and free of side effects when taken in moderate amounts. However, one preliminary report indicates increased heart rate with the use of bromelain.24 In addition, some people are allergic to bromelain. One woman reportedly developed a hives and severe swelling after taking bromelain, even though she had tolerated bromelain on two other occasions previously.25 Because bromelain acts as a blood thinner and little is known about how bromelain interacts with blood-thinning drugs, people should avoid combining such drugs with bromelain in order to reduce the theoretical risk of excessive bleeding.

Are there any drug interactions? Certain medications may interact with bromelain. Refer to the drug interactions safety check for a list of those medications.

References:

1. Izaka K, Yamada M, Kawano T, Suyama T. Gastrointestinal absorption and anti-inflammatory effect of bromelain. Jpn J Pharmacol 1972;22:519–34.

2. Balakrishnan V, Hareendran A, Nair CS. Double-blind cross-over trial of an enzyme preparation in pancreatic steatorrhea. J Assoc Physicians India 1981;29:207–9.

3. Seligman B. Bromelain: an anti-inflammatory agent. Angiology 1962;13:508–10.

4. Cirelli MG. Treatment of inflammation and edema with bromelain. Delaware Med J 1962;34:159–67.

5. Masson M. Bromelain in the treatment of blunt injuries to the musculoskeletal system. A case observation study by an orthopedic surgeon in private practice. Fortschr Med 1995;113:303–6.

6. Levensen S. Supportive therapy in burn care. Debriding agents. J Trauma 1979;19(11 Suppl):8–30.

7. Ahle NW, Hamlet MP. Enzymatic frostbite eschar debridement by bromelain. Ann Emerg Med 1987;16:1063–5.

8. Hayashi M. Pharmacological studies of Shikon and Tooki. (3) Effect of topical application of the ether extracts and Shiunko on inflammatory reactions. Nippon Yakurigaku Zasshi 1977;73:205–14 [in Japanese].

9. Seltzer AP. Minimizing post-operative edema and ecchymoses by the use of an oral enzyme preparation (bromelain). EENT Monthly 1962;41:813–7.

10. Howat RCL, Lewis GD. The effect of bromelain therapy on episiotomy wounds—a double blind controlled clinical trial. J Obstet Gynaecol Br Commonwealth 1972;79:951–3.

11. Zatuchni GI, Colombi DJ. Bromelains therapy for the prevention of episiotomy pain. Obstet Gynecol 1967;29:275–8.

12. Taub SJ. The use of Ananase in sinusitis. A study of 60 patients. EENT Monthly 1966;45:96–8.

13. Ryan RE. A double-blind clinical evaluation of bromelains in the treatment of acute sinusitis. Headache 1967;7:13–7.

14. Mori S, Ojima Y, Hirose T, et al. The clinical effect of proteolytic enzyme containing bromelain and trypsin on urinary tract infection evaluated by double blind method. Acta Obstet Gynaecol Jpn 1972;19:147–53.

15. Cohen A, Goldman J. Bromelains therapy in rheumatoid arthritis. Pennsylvania Med J 1964;67:27–30.

16. Heinicke R, van der Wal L, Yokoyama M. Effect of bromelain (Ananase) on human platelet aggregation. Experientia 1972;28:844–5.

17. Nieper HA. Effect of bromelain on coronary heart disease and angina pectoris. Acta Med Empirica 1978;5:274–8.

18. Seligman B. Oral bromelains as adjuncts in the treatment of acute thrombophlebitis. Angiology 1969;20:22–6.

19. Schafer A, Adelman B. Plasma inhibition of platelet function and of arachidonic acid metabolism. J Clin Invest 1985;75:456–61.

20. Kelly GS. Bromelain: a literature review and discussion of its therapeutic applications. Altern Med Rev 1996;1:243–57 [review].

21. Desser L, Rehberger A, Paukovits W. Proteolytic enzymes and amylase induce cytokine production in peripheral blood mononuclear cells in vitro. Cancer Biother 1994;9:253–63.

22. Munzig E, Eckert K, Harrach T, et al. Bromelain protease F9 reduces the CD44 mediated adhesions of human peripheral blood lymphocytes to human umbilical vein endothelial cells. FEBS Lett 1995;351:215–8.

23. Gaby AR. The story of bromelain. Nutr Healing May 1995:3, 4, 11.

24. Gutfreund AE, Taussig SJ, Morris AK. Effect of oral bromelain on blood pressure and heart rate of hypertensive patients. Hawaii Med J 1978;37:143–6.

25. Nettis E, Napoli G, Ferrannini A, Tursi A. IgE-mediated allergy to bromelain. Allergy 2001;56:257–8.