Oregon Grape - Catapres (Clonidine) Interaction
Herbal: Oregon Grape
Also Known As: Mahonia aquifolium, Barberry, Berberis, Blue Barberry, Creeping Barberry, Holly Barberry, Holly Mahonia, Holly-Leaved Berberis, Mahonia, Mahonia Faux Houx, Mahonia à Feuilles de Houx, Mahonie, Mountain-Grape, Oregon Barberry, Oregon Grape-Holly, Scraperoot
Drug: Clonidine
Brand names:
Catapres
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
May 25, 2025
Interaction Details
Clonidine is classified as belonging to the following category: Antihypertensive Drugs
Theoretically, Oregon grape might increase the risk of hypotension when taken with antihypertensive drugs.
Animal research suggests that berberine, a constituent of Oregon grape, can have hypotensive effects. Also, an analysis of clinical evidence suggests that taking berberine in combination with amlodipine (Norvasc) can lower systolic and diastolic blood pressure when compared with taking amlodipine alone.
Interaction Rating
Likelihood of Occurrence
PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
References
- Sabir M and Bhide NK. Study of some pharmacological actions of berberine. Ind J Physiol & Pharmac 1971;15(3):111-132.
- Chun YT, Yip TT, Lau KL, and et al. A biochemical study on the hypotensive effect of berberine in rats. Gen Pharmac 1979;10:177-182.
- Lan J, Zhao Y, Dong F, et al. Meta-analysis of the effect and safety of berberine in the treatment of type 2 diabetes mellitus, hyperlipemia and hypertension. J Ethnopharmacol. 2015;161:69-81.
Oregon Grape Overview
Oregon grape (Mahonia aquifolium) is a perennial shrub that is native to the Pacific Northwest region of the United States, including Oregon and Washington. It is also found in parts of Canada. The plant is a member of the barberry family (Berberidaceae) and is closely related to the holly plant.
Oregon grape is often grown as an ornamental plant due to its attractive foliage and colorful berries. It is also used medicinally and is believed to have astringent, tonic, and anti-inflammatory properties. The root of the plant is used to make a herbal extract that is used to treat a variety of ailments, including skin conditions, digestive problems, and respiratory conditions. Most of the positive evidence for a medicinal effect is with topical applications as some research has shown topical preparations may modestly decrease the severity of psoriasis. It is important to note that the berries of the plant can be somewhat bitter and may contain toxins, so they should be eaten in moderation.
Clonidine Overview
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Clonidine tablets (Catapres) are used alone or in combination with other medications to treat high blood pressure. Clonidine extended-release (long-acting) tablets (Kapvay) are used alone or in combination with other medications as part of a treatment program to control symptoms of attention deficit hyperactivity disorder (ADHD; more difficulty focusing, controlling actions, and remaining still or quiet than other people who are the same age) in children. Clonidine is in a class of medications called centrally acting alpha-agonist hypotensive agents. Clonidine treats high blood pressure by decreasing your heart rate and relaxing the blood vessels so that blood can flow more easily through the body. Clonidine extended-release tablets may treat ADHD by affecting the part of the brain that controls attention and impulsivity.
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High blood pressure is a common condition and when not treated, can cause damage to the brain, heart, blood vessels, kidneys and other parts of the body. Damage to these organs may cause heart disease, a heart attack, heart failure, stroke, kidney failure, loss of vision, and other problems. In addition to taking medication, making lifestyle changes will also help to control your blood pressure. These changes include eating a diet that is low in fat and salt, maintaining a healthy weight, exercising at least 30 minutes most days, not smoking, and using alcohol in moderation.
Oregon Grape - More Interactions
Oregon Grape interacts with 1189 drugs
Interaction Rating Key
These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.
| Major | The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur. |
| Moderate | Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur. |
| Minor | Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction. |
| Unknown | No interactions have been reported or no interaction data is currently available. |
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Parts of this content are provided by the Therapeutic Research Center, LLC.
DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
© 2021 Therapeutic Research Center, LLC
Drug descriptions are provided by MedlinePlus.
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Dr. Brian Staiger, PharmD
In addition to being a clinical pharmacist specializing in pharmacotherapy, Dr. Brian Staiger is a registered herbalist through the American Herbalist Guild. He has combined his passion for pharmacy practice with the study of medical ethnobotany to improve patient care. Feel free to reach out about any of your herbal or medication questions!
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