Oregano for Drug Interactions

Overseen By Mary F Paine, RPh, PhD

Age: 18 - 65

Sex: Any

Trial Phase: Phase < 1

Sponsor: Washington State University

Must not be taking: Prescription drugs, Supplements

Disqualifiers: Major illness, Mineral deficiency, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 73

16 Participants Needed

Trial Summary

What is the purpose of this trial?

The purpose of this clinical trial is to determine how the supplement oregano affects how the body metabolizes pharmaceutical drugs.

Will I have to stop taking my current medications?

Yes, you must stop taking any medications or supplements that could interfere with the study, as the trial requires participants to not be on any such medications.

What evidence supports the effectiveness of using oregano in combination with other drugs?

The research suggests that herbal ingredients, like those found in oregano, may work together in a synergistic way, meaning they can enhance each other's effects when used together. This could potentially make oregano effective when combined with other drugs, although more specific studies on oregano itself are needed to confirm this. ^{1 2 3 4 5}

What makes the drug cocktail with oregano unique for drug interactions?

The use of oregano in a drug cocktail is unique because it involves a natural herb that may interact with conventional drugs, potentially affecting their metabolism and effectiveness. Unlike synthetic drugs, which usually contain a single active ingredient, oregano as a herbal component can introduce multiple active compounds, increasing the likelihood of interactions. ^{6 7 8 9 10}

Eligibility Criteria

This trial is for individuals interested in how oregano supplements might interact with certain drugs. Specific eligibility criteria are not provided, so it's best to contact the study organizers for detailed requirements.

Inclusion Criteria

Willing to abstain from consuming dietary/herbal supplements and citrus juices for several weeks

I am willing to stop using cannabis, hemp, and THC/CBD products for several weeks.

I can avoid alcohol for 1 day before and on study days.

Exclusion Criteria

Currently using drugs or illicit substances for recreational purposes

I am taking medication or supplements for a mineral deficiency.

I have not used cannabis, hemp, or any CBD/THC products in the last month.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment - Oregano Alone

Participants receive 180 mg of a well-characterized oregano product. Blood and urine samples are collected over 24 hours.

1 day

Multiple visits within 24 hours

Treatment - Drug Cocktail Alone

Participants receive an oral drug cocktail. Blood and urine samples are collected over 24 hours.

1 day

Multiple visits within 24 hours

Treatment - Acute Oregano + Cocktail

Participants receive both the oregano product and the drug cocktail. Blood and urine samples are collected over 24 hours.

1 day

Multiple visits within 24 hours

Treatment - Chronic Oregano + Cocktail

Participants self-administer the oregano product at home for 5 days, followed by administration of the drug cocktail on day 6 with blood and urine collection.

6 days

1 visit on day 6

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

Treatment Details

Interventions

• Drug Cocktail
• Oregano

Trial Overview The study investigates how taking oregano affects the body's ability to process a mix of different drugs (a 'drug cocktail'). This will help understand any potential interactions between oregano and common medications.

Participant Groups

Group I: Arm 4: chronic oregano + cocktail Experimental Treatment 2 Interventions

The same 16 participants will self-administer the oregano product at home for 5 consecutive days. On day 6, participants will return to the study setting, where the procedure described in Arm 3 will be repeated.

Group II: Arm 3: acute oregano + cocktail Experimental Treatment 2 Interventions

The same 16 participants will be administered the oregano product and the drug cocktail. Blood and urine will be collected in the same manner described in Arm 1.

Group III: Arm 2: drug cocktail alone Experimental Treatment 1 Intervention

16 participants, which may or may not include any number of the original 6 from Arm 1, will be administered an oral drug cocktail consisting of caffeine (100 mg), dextromethorphan (30 mg), losartan (25 mg), midazolam syrup (2 mg), and omeprazole (20 mg). Blood and urine will be collected in the same manner described in Arm 1.

Group IV: Arm 1: oregano alone Experimental Treatment 1 Intervention

6 participants will be administered 180 mg of a well-characterized oregano product. Blood will be drawn via an indwelling venous catheter immediately before and at 0.25, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, and 24 hours after administration of oregano. Urine will be collected in multiple jugs for 24 hours.

Who Is Running the Clinical Trial?

Washington State University

Lead Sponsor

Trials

114

Recruited

58,800+

Office of Dietary Supplements (ODS)

Collaborator

Trials

55

Recruited

54,500+

National Center for Complementary and Integrative Health (NCCIH)

Collaborator

Trials

886

Recruited

677,000+

Findings from Research

Many herbal medicines, particularly those identified by Brazil's Unified Public Health System, lack sufficient pharmacokinetic data, which raises concerns about potential herb-drug interactions when used alongside conventional medications.

Most existing studies on these herbal medicines are in vitro, and there is a significant need for more research and monitoring to ensure the safety and efficacy of these treatments in real-world clinical settings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Herbal medicines in Brazil: pharmacokinetic profile and potential herb-drug interactions. Mazzari, AL., Prieto, JM.[2021]

The study highlights two cases of cancer patients using natural compounds alongside chemotherapy, revealing significant risks such as severe adverse drug reactions (ADRs) and potential treatment ineffectiveness due to interactions with prescribed medications.

In one case, a patient experienced neutropenia due to the interaction between chemotherapy and natural products, while in another case, the use of St. John's Wort was avoided to prevent compromising the effectiveness of chemotherapy, emphasizing the importance of careful medication review in cancer treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Toxicity Derived from Interaction between Natural Compounds and Cancer Therapeutic Drugs Metabolized by CYP3A4: Lessons Learned from Two Clinical Case Reports. Orzetti, S., Baldo, P.[2023]

The review highlights that many commonly used herbs can significantly affect the activity of cytochrome P450 (CYP) enzymes and P-glycoprotein (P-gp), which are crucial for drug metabolism and transport.

Understanding how these herbs interact with CYP and P-gp can help optimize drug therapies, as these interactions may alter the effectiveness and safety of various medications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Pharmacokinetic interactions of herbs with cytochrome p450 and p-glycoprotein. Cho, HJ., Yoon, IS.[2020]

A systematic review identified 47 clinical trials examining interactions between natural health products (NHPs) and prescription medications, with an average of 14 participants per study, highlighting the limited research in this area.

Significant drug interactions were primarily observed with St. John wort, which showed potential interactions in 16 out of 24 studies, while other NHPs like garlic and American ginseng also indicated some interactions, but overall data on NHP-drug interactions remains sparse.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Natural health product-drug interactions: a systematic review of clinical trials. Mills, E., Wu, P., Johnston, BC., et al.[2023]

A review of 48 in vivo tests and 106 clinical trials suggests that multi-ingredient synergism in herbal products may contribute to their therapeutic efficacy, with 27 out of 39 cases showing positive interactions at the molecular level.

The findings indicate that the effectiveness of many herbal remedies could be due to the combined effects of multiple ingredients rather than just placebo, highlighting the importance of studying these interactions to understand their mechanisms.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Synergistic therapeutic actions of herbal ingredients and their mechanisms from molecular interaction and network perspectives. Ma, XH., Zheng, CJ., Han, LY., et al.[2009]

Herbal medicine-drug interactions, particularly involving cytochrome P450 enzymes and drug transporters, can significantly affect the safety and efficacy of medications, especially those with a narrow therapeutic index like warfarin and digoxin.

The clinical implications of these interactions are complex and depend on various factors, including the specific herbal medicine used, the conventional drugs involved, and individual patient characteristics, highlighting the need for more controlled studies to better understand these interactions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Drug interactions with herbal medicines. Shi, S., Klotz, U.[2022]

Herb-drug interactions can significantly affect the efficacy and safety of prescription medications, particularly those with a narrow therapeutic index like warfarin and digoxin, often due to metabolic induction or inhibition by herbal medicines.

Common herbs such as garlic, ginkgo, ginseng, and St. John's wort have been shown to interact with various drugs, leading to serious clinical consequences, highlighting the need for careful monitoring and further research on these interactions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Clinical herbal interactions with conventional drugs: from molecules to maladies. Chen, XW., Serag, ES., Sneed, KB., et al.[2019]

Herbal medications are often mistakenly perceived as completely safe due to their natural origins, but they can interact with pharmaceutical drugs, potentially affecting their efficacy and safety.

Understanding the mechanisms behind herb-drug interactions is crucial for healthcare providers to minimize clinical risks, as the concurrent use of herbs and medications can lead to significant safety concerns for patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Medicinal herbs and therapeutic drugs interactions. Alissa, EM.[2014]

Herbal medicines, which contain multiple active ingredients, have a higher potential for interactions with conventional drugs compared to synthetic medications, leading to significant clinical implications.

Certain herbs, like St John's wort, can induce enzymes that lower the effectiveness of various drugs, such as cyclosporine and oral contraceptives, posing risks for patients who rely on these medications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Herb-drug interactions: an overview of the clinical evidence. Izzo, AA.[2007]

The review identified 51 drug-herb interactions from 162 citations, with 22 of these interactions supported by clinical studies, highlighting the need for more research in this area.

Most interactions were pharmacokinetic, particularly affecting drug metabolism via cytochrome P450 enzymes, with warfarin and St. John's wort being the most frequently reported in these interactions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Drug-herb interaction among commonly used conventional medicines: a compendium for health care professionals. Brazier, NC., Levine, MA.[2019]

References

1. Switzerland pubmed.ncbi.nlm.nih.gov

Herbal medicines in Brazil: pharmacokinetic profile and potential herb-drug interactions. [2021]

2. Switzerland pubmed.ncbi.nlm.nih.gov

Toxicity Derived from Interaction between Natural Compounds and Cancer Therapeutic Drugs Metabolized by CYP3A4: Lessons Learned from Two Clinical Case Reports. [2023]

3. United States pubmed.ncbi.nlm.nih.gov

Pharmacokinetic interactions of herbs with cytochrome p450 and p-glycoprotein. [2020]

4. United States pubmed.ncbi.nlm.nih.gov

Natural health product-drug interactions: a systematic review of clinical trials. [2023]

5. England pubmed.ncbi.nlm.nih.gov

Synergistic therapeutic actions of herbal ingredients and their mechanisms from molecular interaction and network perspectives. [2009]

6. Switzerland pubmed.ncbi.nlm.nih.gov

Drug interactions with herbal medicines. [2022]

7. United Arab Emirates pubmed.ncbi.nlm.nih.gov

Clinical herbal interactions with conventional drugs: from molecules to maladies. [2019]

8. United States pubmed.ncbi.nlm.nih.gov

Medicinal herbs and therapeutic drugs interactions. [2014]

9. England pubmed.ncbi.nlm.nih.gov

Herb-drug interactions: an overview of the clinical evidence. [2007]

10. United States pubmed.ncbi.nlm.nih.gov

Drug-herb interaction among commonly used conventional medicines: a compendium for health care professionals. [2019]