Report on Bilberry Side Effects and Usage


Natural health supplements sometimes have unexpected side effects or interactions with medication that can lead to adverse reactions that are sometimes life threatening. The following is a list of cautions that you should be aware of before using bilberry (Vaccinium myrtillus). These are referred to as drug/herb interactions.

Warning 1 – Contraindications: Animal data suggests that those with bleeding disorders, diabetes or hypoglycemia should talk to their doctor before using bilberry.

Warning 2 – Anticoagulants: Bilberry may increase the action of anticoagulants.

Warning 3 – Antidiabetics, oral: This herb may increase hypoglycemia.

Warning 4 – Antiplatelet agents: Bilberry contains a substance that may cause antiaggregation of platelets, which hinders the blood clotting process.

Warning 5 – Aspirin: Bilberry may increase the anticoagulation action of aspirin.

Warning 6 – Insulin: Using bilberry may significantly decrease blood sugar levels – monitor carefully.

Warning 7 – Iron salts: Bilberry interferes with the absorption of iron salts.

Warning 8 – NSAIDs: This herb may increase the action of NSAIDs.

Used as a natural health remedy: bilberry is used internally for the following benefits and conditions:

  • Atherosclerosis
  • Age-related macular degeneration
  • Ocular disorders such as poor night vision, cataracts, and macular degeneration
  • Vascular disorders such as easy bruising
  • Diarrhea
  • Oral irritation
  • Diabetes
  • Improve vision
  • Limiting the progression of cataracts
  • Limiting the progression of diabetic retinopathy
  • Reduce the oxidation of LDL cholesterol
  • Reduce swelling
  • Bilberry has been shown to inhibit platelet aggregation. Platelet aggregation is a contributing factor in the formation of arterial plaques which leads to hardening of the arteries. It is also part of the disease process in clot formation and deep vein thrombosis or blood clots. Because it supports the structure and integrity of the blood vessels and limits platelet aggregation, bilberry may be helpful for cases of deep vein blood clots.
  • Bilberry may be effective in the treatment of certain types of cancers. In one study, bilberry extract was shown to inhibit new blood vessel formation. Invasive cancers use the process of blood vessel formation to increase blood supply, which supplies specific nutrients needed for tumor growth and subsequent invasion of surrounding tissue. The fruit was also shown to slow the growth of colon cancer cells in test tubes. And, the fruit did not interfere with the growth of normal healthy colon cells in the test.

Side Effects of bilberry

There are no known side effects of using bilberry.

As with any herb, a serious allergic reaction is possible. Seek immediate medical attention if you notice any symptoms of a serious allergic reaction. These may include a rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, or trouble breathing.

Bilberry is also called huckleberry, European blueberry, whortleberry, trackleberry, dyeberry, and wineberry.

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