Bromelain is a mixture of protein-digesting (proteolytic) enzymes found in pineapples (Ananas comosus ). Pineapple has been used for centuries in Central and South America to treat indigestion and reduce inflammation. Bromelain, which is derived from the stem and juice of the pineapple, was first isolated from the pineapple plant in the late 1800s. It is approved by the German Commission E to treat swelling and inflammation following surgery, particularly sinus surgery.

Bromelain can be useful in treating a wide range of conditions, but it is particularly effective in reducing inflammation associated with infection and injuries.

Surgical Procedures and Sports Injuries

Although studies show mixed results, bromelain may reduce swelling, bruising, healing time, and pain following surgery and physical injuries. It is often used to reduce inflammation associated with tendinitis, sprains and strains, and other minor muscle injuries.

Wounds and Burns

Some studies of animals indicate that bromelain (applied to the surface of the skin) may be useful in removing dead tissue (debridement) from third-degree burns. In addition, a preliminary study using a debridement agent that is derived from bromelain to treat people with second- and third-degree burns showed a benefit. Bromelain may also be applied topically to reduce swelling from insect bites and stings.

Sinusitis (Sinus inflammation)

Although not all studies agree, bromelain may help reduce cough and nasal mucus associated with sinusitis, and relieve the swelling and inflammation caused by hay fever. Bromelain is approved by the German Commission E for the treatment of sinus and nasal swelling following ear, nose, and throat surgery or trauma.

Indigestion

Bromelain can digest proteins and may help relieve stomach upset or heartburn, particularly when used in conjunction with other enzymes such as amylase (which digests starch) and lipase (which digests fat). One animal study suggests that the antibacterial effects of bromelain may help to control diarrhea caused by bacteria. However, human studies are needed.

Arthritis and other Inflammatory Conditions

Studies show mixed results, but one study suggested that a combination of bromelain, rutosid, and trypsin was as effective as some commonly used nonsteroidal anti-inflammatory (NSAID) medications for reducing pain associated with osteoarthritis. NSAIDs include ibuprofen (Advil or Motrin), naproxen (Aleve), and diclofenac (Voltaren), among others. Similarly, preliminary studies suggest that bromelain may also help reduce pain associated with rheumatoid arthritis, but the results are not definitive.

Infection

Some evidence from test tubes and animals suggests that bromelain can kill some viruses and bacteria. That could make it a useful addition to conventional treatment of bronchitis, pneumonia, and urinary tract infections. But more research, including human studies, is needed to see whether it is truly effective.

Bromelain is found in the common pineapple plant, but not in high enough doses to have a medicinal effect.

Bromelain is available in tablet or capsule form for oral use. A topical variety is sometimes used by health care providers to treat severe burns. You should never attempt to treat a severe burn yourself; always seek medical attention.

Pediatric

Because there are no known scientific studies on the pediatric use of bromelain, it should not be given to children.

Adults

The German Commission E recommends 80 - 320 mg two to three times per day. For specific conditions, higher doses may be prescribed:

• Digestive aid: 500 mg per day in divided doses with meals
• Injuries: 500 mg four times a day on an empty stomach
• Arthritis: 500 - 2,000 mg a day in two divided doses

Because supplements may have side effects or interact with medications, they should be taken only under the supervision of a knowledgeable health care provider. Bromelain is generally recommended for no longer than 8 - 10 days in a row.

Side effects from bromelain are generally mild and include nausea, vomiting, diarrhea, and excessive menstrual bleeding.

People who are allergic to pineapples should not take bromelain because skin reactions or asthma-like symptoms may occur.

Pregnant women and people with bleeding disorders, high blood pressure, and liver or kidney disease should not take bromelain.

If you are currently being treated with any of the following medications, you should not use bromelain without talking to your health care provider.

Antibiotics -- Bromelain may increase the amount of antibiotics absorbed by the body. In one clinical study, the combination of bromelain and amoxicillin increased the levels of amoxicillin in the blood. Also, some studies suggest that bromelain may increase the body's absorption of tetracycline, but results of other studies have been conflicting.

Anticoagulants and antiplatelet drugs (blood-thinners) -- Bromelain may affect the blood's ability to clot, and could interfere with any blood-thinning drugs you are taking, including:

• Warfarin (Coumadin)
• Clopidogrel (Plavix)
• Aspirin

Sedatives -- Some experts believe bromelain may increase the effect of drugs that have a sedating effect, including:

• Anticonvulsants such as phenytoin (Dilantin) and valproic acid (Depakote)
• Barbiturates
• Benzodiazepines such as alprazolam (Xanax) and diazepam (Valium)
• Drugs to treat insomnia, such as zolpidem (Ambien), zaleplon (Sonata), eszopiclone (Lunesta), and ramelteon (Rozerem)
• Tricyclic antidepressants such as amitriptyline (Elavil)
• Alcohol

The same is true of herbs with a sedating effect, such as valerian, kava, and catnip.

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