Background

Oregon grape (Mahonia aquifolium) is a plant native to the western coast of North America. It has a history of use in American folk medicine.

Oregon grape contains chemicals that might help fight bacterial and fungal infections. Oregon grape might also reduce inflammation from skin conditions such as psoriasis.

People use Oregon grape for scaly, itchy skin (psoriasis). It is also used for eczema, indigestion, and many other conditions, but there is no good scientific evidence to support these uses.

Oregon grape is sometimes called Oregon barberry. Don't confuse Oregon grape with European barberry. These are not the same.

Safety Safety definitions

When taken by mouth: Oregon grape is commonly consumed in foods. But there isn't enough reliable information to know if Oregon grape is safe to use in larger amounts as medicine or what the side effects might be.

When applied to the skin: Oregon grape is possibly safe when a specific 10% Oregon grape cream (Relieva, Apollo Pharmaceutical) is used for up to 12 weeks. Side effects might include itching, burning, irritation, and allergic reactions.

Special Precautions & Warnings:

Pregnancy: Oregon grape Is likely unsafe when taken by mouth during pregnancy. Oregon grape contains a chemical called berberine, which might cause harm to the fetus.

Breast-feeding: Oregon grape is likely unsafe when taken by mouth while breast-feeding. Oregon grape contains a chemical called berberine, which can be transferred to the infant through breast milk.

Children: Oregon grape is likely unsafe when given to infants by mouth. The berberine in Oregon grape can cause brain damage in newborns, particularly premature newborns who have jaundice. There isn't enough reliable information to know if Oregon grape is safe when used by older children.

Effectiveness

Dosing & administration

Oregon grape has most often been applied to the skin as a topical cream in adults. Speak with a healthcare provider to find out what type of product and dose might be best for a specific condition.

Interactions with pharmaceuticals

Cyclosporine (Neoral, Sandimmune)

Interaction Rating=Moderate Be cautious with this combination.

The body breaks down cyclosporine to get rid of it. Oregon grape might decrease how fast the body breaks down cyclosporine. This might cause there to be too much cyclosporine in the body and potentially cause side effects.

Medications changed by the liver (Cytochrome P450 2C9 (CYP2C9) substrates)

Interaction Rating=Moderate Be cautious with this combination.

Some medications are changed and broken down by the liver. Oregon grape might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.

Medications changed by the liver (Cytochrome P450 2D6 (CYP2D6) substrates)

Interaction Rating=Moderate Be cautious with this combination.

Some medications are changed and broken down by the liver. Oregon grape might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.

Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates)

Interaction Rating=Moderate Be cautious with this combination.

Some medications are changed and broken down by the liver. Oregon grape might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.

Medications for diabetes (Antidiabetes drugs)

Interaction Rating=Moderate Be cautious with this combination.

Oregon grape might lower blood sugar levels. Taking Oregon grape along with diabetes medications might cause blood sugar to drop too low. Monitor your blood sugar closely.

Medications for high blood pressure (Antihypertensive drugs)

Interaction Rating=Moderate Be cautious with this combination.

Oregon grape might lower blood pressure. Taking Oregon grape along with medications that lower blood pressure might cause blood pressure to go too low. Monitor your blood pressure closely.

Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)

Interaction Rating=Moderate Be cautious with this combination.

Oregon grape might slow blood clotting. Taking Oregon grape along with medications that also slow blood clotting might increase the risk of bruising and bleeding.

Sedative medications (CNS depressants)

Interaction Rating=Moderate Be cautious with this combination.

Oregon grape might cause sleepiness and slowed breathing. Some medications, called sedatives, can also cause sleepiness and slowed breathing. Taking Oregon grape with sedative medications might cause breathing problems and/or too much sleepiness.

Interactions with herbs & supplements

Herbs and supplements that might lower blood pressure: Oregon grape might lower blood pressure. Taking it with other supplements that have the same effect might cause blood pressure to drop too much. Examples of supplements with this effect include andrographis, casein peptides, L-arginine, niacin, and stinging nettle.
Herbs and supplements that might lower blood sugar: Oregon grape might lower blood sugar. Taking it with other supplements with similar effects might lower blood sugar too much. Examples of supplements with this effect include aloe, bitter melon, cassia cinnamon, chromium, and prickly pear cactus.
Herbs and supplements that might slow blood clotting: Oregon grape might slow blood clotting and increase the risk of bleeding. Taking it with other supplements with similar effects might increase the risk of bleeding in some people. Examples of supplements with this effect include garlic, ginger, ginkgo, nattokinase, and Panax ginseng.
Herbs and supplements with sedative properties: Oregon grape might cause sleepiness and slowed breathing. Taking it along with other supplements with similar effects might cause too much sleepiness and/or slowed breathing in some people. Examples of supplements with this effect include hops, kava, L-tryptophan, melatonin, and valerian.

Interactions with foods

There are no known interactions with foods.