Grape Seed Extract (GRAPE) Overview Information
Grapes are the fruit of a vine (Vitis vinifera). The whole fruit, skin, leaves and seed of the grape plant are used as medicine. Grape seeds are by-products of the manufacturing of wine. Be careful not to confuse grape with grapefruit, and other similar sounding medicines.
Grape is used for preventing diseases of the heart and blood vessels, varicose veins, hemorrhoids, “hardening of the arteries” (atherosclerosis), high blood pressure, swelling after injury or surgery, heart attack, and stroke.
Some people also use grape as a mild laxative for constipation. You have probably heard of grape “fasts” as part of “detoxification.”
Grape seed is used for diabetes complications such as nerve and eye problems, improving wound healing, preventing tooth decay, preventing cancer, an eye disease called age-related macular degeneration (AMD), poor night vision, liver disorders, and hay fever.
Dried grapes, raisins, or sultanas (white raisins) are used for cough.
Grape leaf is used for attention deficit-hyperactivity disorder (ADHD), chronic fatigue syndrome (CFS), diarrhea, heavy menstrual bleeding, uterine bleeding, and canker sores.
Grape leaf is used as a food, particularly in Greek cooking.
How does it work?
Grape contains flavonoids, which can have antioxidant effects, lower the levels of low density lipoproteins (LDLs, or “bad cholesterol”), relax blood vessels, and reduce the risk of coronary heart disease. The antioxidants in grape might help to prevent heart disease and have other potentially beneficial effects. Red grape varieties provide more antioxidants than white or blush grape varieties.
Grape leaf might reduce inflammation and have astringent effects. In other words, grape leaf seems to be able to draw tissue together, which could help stop bleeding and diarrhea. These properties appear to be greatest in the red leaves.
Possibly Effective for:
- Circulation problems, such as poor blood flow in the legs (chronic venous insufficiency) that can cause the legs to swell. Taking grape seed extract seems to reduce symptoms such as tired or heavy legs, tension, and tingling and pain.
- Decreasing eye stress from glare.
Possibly Ineffective for:
- Hay fever and seasonal nasal allergies.
- Preventing heart disease. There is some evidence drinking grape juice or red wine might help to prevent heart disease.
- High blood pressure. Early research suggests that grape seed does not have a significant effect on blood pressure in people with high blood pressure.
- Poor night vision. Preliminary research suggests grape seed extract containing chemicals called proanthocyanidins might improve night vision.
- Treating varicose veins.
- Attention deficit-hyperactivity disorder (ADHD).
- Chronic fatigue syndrome (CFS).
- Heavy menstrual periods.
- Age-related macular degeneration (AMD).
- Canker sores.
- Liver damage.
- High cholesterol levels.
- Metabolic syndrome (a cluster of conditions that put people at high risk for heart disease).
- Other conditions.
Grape Seed Extract (GRAPE) Side Effects & Safety
Grape is LIKELY SAFE for most people. Eating large quantities of grapes, dried grapes, raisins, or sultanas might cause diarrhea. Some people have allergic reactions to grapes and grape products.
Some other potential side effects include stomach upset, indigestion, nausea, vomiting, cough, dry mouth, sore throat, infections, headache, and muscular problems.
Special Precautions & Warnings:Pregnancy and breast-feeding: Not enough is known about the use of grape in medicinal amounts (supplements or amounts that are higher than normal food amounts) during pregnancy and breast-feeding. Stay on the safe side and avoid use.
Moderate Interaction Be cautious with this combination
- Medications changed by the liver (Cytochrome P450 1A2 (CYP1A2) substrates) interacts with GRAPE
Some medications are changed and broken down by the liver.
Grape juice might increase how quickly the liver breaks down some medications. Taking grape along with some medications that are changed by the liver can decrease the effectiveness of some medications. Before taking grape talk to your healthcare provider if you take any medications that are changed by the liver.
Some of these medications that are changed by the liver include clozapine (Clozaril), cyclobenzaprine (Flexeril), fluvoxamine (Luvox), haloperidol (Haldol), imipramine (Tofranil), mexiletine (Mexitil), olanzapine (Zyprexa), pentazocine (Talwin), propranolol (Inderal), tacrine (Cognex), theophylline, zileuton (Zyflo), zolmitriptan (Zomig), and others.
- Phenacetin interacts with GRAPE
The body breaks down phenacetin to get rid of it. Drinking grape juice might increase how quickly the body breaks down phenacetin. Taking phenacetin along with grape juice might decrease the effectiveness of phenacetin.
- Warfarin (Coumadin) interacts with GRAPE
Warfarin (Coumadin) is used to slow blood clotting. Grape seed might also slow blood clotting. Taking grape seed along with warfarin (Coumadin) might increase the chances of bruising and bleeding. Be sure to have your blood checked regularly. The dose of your warfarin (Coumadin) might need to be changed.
Grape Seed Extract (GRAPE) Dosing
The following doses have been studied in scientific research:
- For poor blood flow in the legs (chronic venous insufficiency):
- Standardized red vine grape extract AS 195 (Antistax, Boehringer Ingelheim 360 mg or 720 mg once daily.
- Grape seed extract as tablets or capsules dosed at 75-300 mg daily for three weeks followed by a maintenance dose of 40-80 mg daily.
- Grape seed extract proanthocyanidin doses of 150-300 mg per day. Proanthocyanidin is one of the active ingredients in grape.
- For reducing eye stress due to glare: Grape seed extract proanthocyanidin doses of 200-300 mg per day.