Oregano - Rituxan (Rituximab) Interaction
Herbal: Oregano
Also Known As: Origanum vulgare, Carvacrol, European Oregano, Marjolaine Sauvage, Marjolaine Vivace, Mediterranean Oregano, Mountain Mint, Oil of Oregano, Oregano Oil, Organy, Origan, Origan Européen, Origani Vulgaris Herba, Origano, Winter Marjoram, Wintersweet
Drug: Rituximab
Brand names:
Rituxan
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
May 18, 2025
Interaction Details
There were no interactions found between Rituximab and Oregano. This does not mean the potential for an interaction does not exist, however. There is often a lack of studies and data surrounding traditional medicine, especially concerning drug interactions, so it is important to always consult your provider before making any changes to your medication regimen.
Pharmacist Analysis
Oregano (and oregano oil) supplements are generally considered safe and there is no indication that there is an interaction between the drug highlighted in this interaction monograph and oregano.
However, as with all supplements, it is important to talk to your doctor before starting anything new, so you can be appropriately monitored.
In terms of drug interactions that have been reported with oregano, below are some examples.
Anticoagulant; Antiplatelet Drugs
Anticoagulants and antiplatelet drugs work by slowing down or preventing blood clotting. While they are essential medications for individuals with certain conditions, they come with an increased risk of bleeding.
Some studies have reported that oregano oil may also increase the risk of bleeding, as it contains compounds that have antithrombin activity and can inhibit platelet aggregation.
Therefore, taking oregano oil along with anticoagulants or antiplatelet drugs may increase the risk of bleeding, bruising, and other adverse effects.
Anti-Diabetic Drugs
Several studies suggest that oregano supplements may help lower blood glucose (i.e., sugar) levels. In vitro and animal research has shown that oregano extracts might stimulate glucose uptake and reduce blood glucose levels.
Therefore, based on the available evidence, combining oregano oil with antidiabetic drugs could potentially cause blood sugar levels to drop too low, leading to hypoglycemia.
However, it is important to note that studies reporting that oregano can reduce blood glucose levels have not reported it causing hypoglycemia.
References
- Anti-hyperglycaemic activity of the aqueous extract of Origanum vulgare growing wild in Tafilalet region. PubMed
- Inhibitory effect of clonal oregano extracts against porcine pancreatic amylase in vitro. PubMed
- Antithrombin activity of some constituents from Origanum vulgare. PubMed
- Comparative screening of plant essential oils: phenylpropanoid moiety as basic core for antiplatelet activity. PubMed
Oregano Overview
Oregano is a perennial herb that is native to the Mediterranean region. It is a member of the mint family (Lamiaceae) and is known for its fragrant leaves and small, purple flowers.
Oregano is commonly used in cooking and has a strong, slightly bitter flavor.
In traditional medicine, oregano is believed to have a number of health benefits due to its high content of antioxidant and possible antimicrobial properties. It is thought to have anti-inflammatory and pain-relieving effects, and it is used to treat a variety of conditions, including cardiovascular disease, digestive problems, respiratory infections, and skin disorders.
Most dietary supplements containing oregano are oregano oil extracts, often standardized to contain a specific amount of certain components, such as carvacrol.
Rituximab Overview
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Rituximab injection products are used in adults alone or with other medications to treat various types of non-Hodgkin's lymphoma (NHL; a type of cancer that begins in a type of white blood cells that normally fights infection). Rituximab injection products are also used in adults with other medications to treat chronic lymphocytic leukemia (CLL; a type of cancer of the white blood cells). Rituximab injection products (Rituxan, Ruxience, Truxima) are also used in adults with methotrexate (Otrexup, Rasuvo, Xatmep, others) to treat the symptoms of rheumatoid arthritis (RA; a condition in which the body attacks its own joints, causing pain, swelling, and loss of function) in adults who have already been treated with a certain type of medication called a tumor necrosis factor (TNF) inhibitor. Rituximab injection products (Rituxan, Riabni, Ruxience, Truxima) are also used in adults and children 2 years of age and older along with other medications to treat granulomatosis with polyangiitis (Wegener's granulomatosis) and microscopic polyangiitis, which are conditions in which the body attacks its own veins and other blood vessels, which causes damage to organs, such as the heart and lungs. Rituximab injection (Rituxan) is used to treat pemphigus vulgaris (a condition that causes painful blisters on the skin and the lining the mouth, nose, throat and genitals). Rituximab injection products are in a class of medications called monoclonal antibodies. They treat the various types of NHL and CLL by killing cancer cells. Certain rituximab injection products also treat rheumatoid arthritis, granulomatosis with polyangiitis, microscopic polyangiitis, and pemphigus vulgaris by blocking the activity of the part of the immune system that may damage the joints, veins, and other blood vessels.
Oregano - More Interactions
Oregano interacts with 205 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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