Several preliminary trials have reported reduced pain and swelling, and/or faster healing in people with a variety of conditions using either bromelain,¹ papain from papaya, ^2,3 or a combination of trypsin and chymotrypsin.⁴ Double-blind trials have reported faster recovery from athletic injuries, including sprains and strains, and earlier return to activity using eight tablets daily of trypsin/chymotrypsin,^5,6,7,8 four to eight tablets daily of papain,⁹ eight tablets of bromelain (single-blind only),¹⁰ or a combination of these enzymes.¹¹ However, one double-blind trial using eight tablets per day of trypsin/chymotrypsin to treat sprained ankles found no significant effect on swelling, bruising, or overall function.¹²

Bromelain is measured in MCUs (milk clotting units) or GDUs (gelatin dissolving units). One GDU equals 1.5 MCU. Strong products contain at least 2,000 MCU (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, because 500 mg is half a gram. Some doctors recommend 3,000 MCU taken three times per day for several days, followed by 2,000 MCU three times per day. Some of the research, however, uses smaller amounts, such as 2,000 MCU taken in divided amounts in the course of a day (500 MCU taken four times per day).

Supplementation with bromelain, an enzyme derived from pineapple stem, prior to and following a surgical procedure has been shown to reduce swelling, bruising, healing time, and pain.¹³ Bromelain supplementation has also been shown to accelerate the healing of soft-tissue injuries in male boxers.¹⁴ The amount of bromelain used in these studies was 40 mg four times per day, in the form of enteric-coated tablets. Enteric-coating prevents the stomach acid from partially destroying the bromelain. Most currently available bromelain products are not enteric-coated, and it is not known if such products would be as effective as enteric-coated bromelain.

Bromelain, a proteolytic enzyme, 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.^15,16,17

Proteolytic enzymes, including bromelain, papain, trypsin, and chymotrypsin, may be helpful in healing minor injuries because they have anti-inflammatory activity and are capable of being absorbed from the gastrointestinal tract.^18,19,20 Several preliminary trials have reported reduced pain and swelling, and/or faster healing in people with a variety of conditions who use either bromelain^21,22,23 or papain.^24,25,26

Bromelain, an enzyme derived from pineapple, has been reported to relieve symptoms of acute sinusitis. In a double-blind trial, 87% of patients who took bromelain reported good to excellent results compared with 68% of those taking placebo.²⁷ Other double-blind research has shown that bromelain reduces symptoms of sinusitis.^28,29 Research with bromelain for sinusitis generally uses the enteric-coated form. Enteric-coating prevents the stomach juices from partially destroying the bromelain. Most commercially available bromelain products today are not enteric-coated, and it is not known how the potency of these different products compares.

Studies conducted in the past have used bromelain compounds with therapeutic strengths measured in units called Rorer units (RU). Potency of contemporary bromelain compounds are quantified in either MCUs (milk clotting units) or GDUs (gelatin dissolving units); one GDU equals 1.5 MCU. One gram of bromelain standardized to 2,000 MCU would be approximately equal to 1 gram with 1,200 GDU of activity, or 8 grams with 100,000 RU of activity. Physicians sometimes recommend 3,000 MCU taken three times per day for several days, followed up by 2,000 MCU per day.³⁰ Much of the research conducted has used smaller amounts likely to be the equivalent (in modern units of activity) of approximately 500 MCU taken four times a day.

Bromelain reduces the thickness of mucus, which may be beneficial for those with asthma,³¹ though clinical actions in asthmatics remain unproven.

Supplementation with bromelain, an enzyme derived from pineapple stem, prior to and following a surgical procedure has been shown to reduce swelling, bruising, healing time, and pain.³² Bromelain supplementation has also been shown to accelerate the healing of soft-tissue injuries in male boxers.³³ The amount of bromelain used in these studies was 40 mg four times per day, in the form of enteric-coated tablets. Enteric-coating prevents the stomach acid from partially destroying the bromelain. Most currently available bromelain products are not enteric-coated, and it is not known if such products would be as effective as enteric-coated bromelain.

Quercetin, a flavonoid with anti-inflammatory and antioxidant effects, has recently been reported to improve symptoms of NBP and PD. An uncontrolled study reported that 500 mg of quercetin twice daily for at least two weeks significantly improved symptoms in 59% of men with chronic prostatitis.³⁴ These results were confirmed in a double-blind study, in which similar treatment with quercetin for one month improved symptoms in 67% of men with NBP or PD.³⁵ Another uncontrolled study combined 1,000 mg per day of quercetin with the enzymes bromelain and papain, resulting in significant improvement of symptoms.³⁵ Bromelain and papain promote absorption of quercetin and have anti-inflammatory effects as well.³⁷

The proteolytic enzymes, bromelain (from pineapple) and trypsin may enhance the effectiveness of antibiotics in people with a UTI. In a double-blind trial, people with UTIs received antibiotics plus either bromelain/trypsin in combination (400 mg per day for two days) or a placebo. One hundred percent of those who received the enzymes had a resolution of their infection, compared with only 46% of those given the placebo.³⁷ This study used enteric-coated tablets. Enteric-coating prevents stomach acid from partially destroying the bromelain. Most commercially available bromelain products today are not enteric-coated, and it is not known if non-enteric coated preparations would be as effective.

Proteolytic enzymes, including bromelain, papain, trypsin, and chymotrypsin, may be helpful in healing minor injuries because they have anti-inflammatory activity and are capable of being absorbed from the gastrointestinal tract.^38,39,40 Several preliminary trials have reported reduced pain and swelling, and/or faster healing in people with a variety of conditions who use either bromelain^41,42,43 or papain.^44,45,46

Bromelain has significant anti-inflammatory activity. Many years ago in a preliminary trial, people with RA who were given bromelain supplements experienced a decrease in joint swelling and improvement in joint mobility.⁴⁷ The amount of bromelain used in that trial was 20–40 mg, three or four times per day, in the form of enteric-coated tablets. The authors provided no information about the strength of activity in the bromelain supplements that were used. (Today, better quality bromelain supplements are listed in gelatin-dissolving units [GDU] or in milk-clotting units [MCU].) Enteric-coating protects bromelain from exposure to stomach acid. Most commercially available bromelain products today are not enteric-coated.

Bromelain has been reported in a preliminary study to relieve angina. In that study, 600 people with cancer were receiving bromelain (400 to 1,000 mg per day). Fourteen of those individuals had been suffering from angina. In all 14 cases, the angina disappeared within 4 to 90 days after starting bromelain.⁴⁸ However, as there was no control group in the study, the possibility of a placebo effect cannot be ruled out. Bromelain is known to prevent excessive stickiness of blood platelets,⁴⁹ which is believed to be one of the triggering factors for angina.