Indications
Proanthocyanidins are natural plant compounds (a type of flavonoid) found in pine bark, grape seeds, cranberries, cocoa and some fruits. As a supplement they are used as antioxidants, to support healthy blood vessels and circulation, for symptoms of poor vein circulation in the legs such as heaviness and swelling, and, in the case of cranberry extracts, to help reduce the chance of repeated urinary tract infections in women. Scientific evidence for these uses is promising but limited.
How It Works
Proanthocyanidins neutralise free radicals, unstable molecules that can damage cells. They may help strengthen the walls of small blood vessels, support the production of nitric oxide that relaxes blood vessels, and reduce inflammation. Cranberry proanthocyanidins may make it harder for certain bacteria to stick to the lining of the bladder.
Dosage and Administration
Take as directed on the label or by your doctor, usually once or twice a day with water, with or after food. The amount of proanthocyanidin differs widely between products and plant sources, so do not switch products without checking the strength.
Interactions
Proanthocyanidin supplements may slightly increase the risk of bleeding when taken with blood thinners such as Warfarin, Aspirin or Clopidogrel. They may lower blood sugar and add to the effect of diabetes medicines. Pine bark extract may affect the immune system and could interfere with immunosuppressants such as Ciclosporin. Tell your doctor about any supplement you take.
Contraindications
Do not use if you are allergic to the plant source (for example pine, grape or cranberry) or to any other ingredient. People with bleeding disorders or autoimmune diseases should ask a doctor first.
Side Effects
Proanthocyanidins are usually well tolerated. Possible side effects include:
- Stomach upset, nausea or diarrhoea
- Headache or dizziness
- Mouth ulcers or bad breath, reported rarely
Get urgent medical help for unusual bleeding or bruising, or signs of an allergic reaction such as rash, swelling of the face or throat, or difficulty breathing.
Pregnancy and Lactation
There is not enough reliable information on the safety of concentrated proanthocyanidin supplements in pregnancy or breastfeeding. Normal amounts in food are fine, but use supplements only if your doctor advises them.
Precautions and Warnings
Stop taking the supplement about 2 weeks before planned surgery because of the possible bleeding effect. A supplement does not treat an active urinary infection: see a doctor if you have burning when passing urine, fever or back pain. Leg swelling can have serious causes, so get it checked. Keep away from children.
Overdose
Large amounts may cause stomach upset and diarrhoea. Serious poisoning is not expected, but contact a doctor if a large amount has been taken or a child has swallowed it.
Therapeutic Class
Dietary supplement (plant flavonoid antioxidant).
Storage
Store below 30°C in a dry place, away from light and out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.