Herbal Medicine, Supplements and Self-Medication in Dentistry

Herbal Medicine, Dietary Supplements and Self-Medication – DentoLink

The under-reporting problem

A frequent blind spot in the medical history

Herbal dietary supplements are widely perceived by the public as "natural" and therefore harmless products, unrelated to conventional prescription drugs — a perception that largely explains their massive under-reporting during medical interviews, including before a surgical procedure.

A study of patients presenting for surgery showed that while nearly 5% were taking an herbal supplement, only two cases out of more than 130 had been recorded in their medical chart before the intervention — illustrating the scale of the traceability problem.

Why this under-reporting is a genuine clinical problem

Some herbs have confirmed drug interactions, others are suspected based on solid preclinical data, or are commonly recognized as major interactions — potentially leading to severe adverse events. The "natural" label on a product is in no way a guarantee of pharmacological safety.

Herbs with documented bleeding risk

Several commonly consumed herbs and supplements affect coagulation or platelet function through varied mechanisms, with uneven levels of evidence. This dimension is directly relevant to oral surgery, adding to the already documented risk of antithrombotic therapy (see dedicated articles on DOACs, VKAs, and antiplatelet agents).

Garlic (Allium sativum)

High level of evidence — confirmed association

A systematic review concluded, based on pooled data, that garlic does in fact predispose to surgical bleeding
Antiplatelet effect through inhibition of aggregation
Robust association independent of concurrent anticoagulant use

Ginkgo biloba

Solid evidence of bleeding risk

Inhibition of platelet-activating factor — a mechanism distinct from NSAIDs or aspirin
Association with surgical bleeding documented across several reviews, particularly in combination with anticoagulant therapy
Commonly used for mild cognitive decline and memory — the typical user profile is often older, a population already at increased bleeding risk (see article on polypharmacy)

Ginseng

Reported antiplatelet effect

Antiplatelet properties reported, in addition to a potential effect on blood glucose (see Section 05)
Frequently consumed as a stimulant or general tonic

Other herbs to watch

Weaker or inconsistent association

Hawthorn: strong association with surgical bleeding according to some recent data
Turmeric, ginger, fish oil/omega-3, vitamin E: coagulation effects reported, with variable levels of evidence across studies
Echinacea, aloe vera: weaker or inconsistent association with surgical bleeding

St. John's Wort: the major enzyme inducer

The most problematic herb in terms of drug interactions

St. John's Wort (Hypericum perforatum), traditionally used for mild to moderate depression and anxiety, is a potent inducer of the CYP3A4 cytochrome and the P-glycoprotein transporter. This enzymatic induction reduces the effective concentration of numerous drugs metabolized through this pathway — an interaction mechanism affecting roughly forty molecules by some estimates.

Drug affected	Consequence of the interaction with St. John's Wort
Warfarin (VKA)	Reduced anticoagulant effect — thrombotic risk
Oral contraceptives	Reduced contraceptive efficacy — risk of unintended pregnancy
Cyclosporine, tacrolimus (immunosuppressants)	Risk of graft rejection due to underdosing
Digoxin	Reduced plasma concentration
Theophylline	Reduced plasma concentration

General recommendationIt is strongly recommended to completely avoid combining St. John's Wort with any prescription or over-the-counter medication, given the scale and unpredictability of its interactions. Any patient reporting the use of St. John's Wort, regardless of the dental reason for the visit, warrants a systematic review of their entire current medication regimen.

Other relevant pharmacokinetic interactions

Herb / supplement	Mechanism	Dental relevance
Echinacea	CYP3A4 inhibition	Possible interactions with certain antibiotics and antifungals metabolized via this pathway
Goldenseal	Potent CYP3A4 inhibition	Significant drug interactions to consider, comparable to grapefruit
Kava	Potentiation of anesthesia's sedative effects	Prolongs the effects of anxiolytic premedication and sedation (see dedicated article)
Valerian	Interferes with anesthesia medications, prolongs sedation	Relevant for in-office conscious sedation — inform the patient

Cardiovascular and glycemic effects

Cardiovascular instability

Ephedra, ginseng, and kava have been associated with intraoperative cardiovascular instability (tachycardia, hypertension, arrhythmia) — relevant in cases of sedation or anesthesia with a vasoconstrictor (see dedicated article).

Hypotension

Garlic, coenzyme Q10, and L-arginine can lower blood pressure — a factor to consider in patients already treated for hypertension or when sedation is planned.

Hypoglycemia

Ginseng, chromium, fenugreek, and bitter melon can lower blood glucose — particularly relevant for diabetic patients, especially during a preoperative fasting period.

Discontinuation timing before oral surgery

General recommendation from anesthesiology societies

The American Society of Anesthesiologists (ASA) and the American Association of Nurse Anesthetists (AANA) classically recommend discontinuing herbal supplements 1 to 2 weeks before an elective surgical procedure, given the variability and uncertainty surrounding their metabolism and clearance.

A necessary nuance for ambulatory oral surgery

This general recommendation, derived primarily from the context of major surgery, must be weighted for routine, low bleeding-risk oral surgery procedures (simple extraction, scaling and root planing, single implant placement) — in the same way as for conventional anticoagulants and antiplatelet agents (see dedicated articles), where continuing treatment is generally preferred for low-risk procedures, with reinforced local hemostasis rather than systematic discontinuation.

For high bleeding-risk procedures

Complex oral surgery, multiple extractions, implant surgery with bone grafting — discontinuation 1 to 2 weeks before the procedure for herbs with documented bleeding risk (garlic, ginkgo, ginseng) is reasonable, in consultation with the treating physician if the supplement addresses a specific therapeutic indication.

For low-risk procedures

Continuation without interruption is possible, applying the standard local hemostasis protocol (see dedicated article) — consistent with the approach already adopted for conventional antithrombotics in routine procedures.

Summary table by herb

Herb / supplement	Main risk	Level of evidence	Approach before high-risk oral surgery
Garlic	Bleeding	High	Discontinue 1-2 weeks prior
Ginkgo biloba	Bleeding	High	Discontinue 1-2 weeks prior
Ginseng	Bleeding + hypoglycemia	Moderate	Discontinue 1-2 weeks prior
St. John's Wort	Major CYP3A4/P-gp interactions	High	Systematic review of concurrent medications
Kava, Valerian	Potentiation of sedation/anesthesia	Moderate	Inform patient if sedation planned
Turmeric, ginger, omega-3, vitamin E	Bleeding (variable)	Variable	Caution for high-risk procedures
Echinacea	CYP3A4 interactions (inhibition)	Moderate	Check associated antibiotics/antifungals

Non-herbal self-medication to ask about

Beyond herbs, other forms of self-medication must be systematically investigated, as they directly interfere with routine dental prescriptions.

Over-the-counter NSAIDs and aspirin

Taken as self-medication for dental pain before the consultation, without being spontaneously mentioned — risk of cumulative dosing or interaction with the practitioner's prescription (see dedicated NSAID article).

High-dose vitamin E and fish oil

Have their own antiplatelet properties, often overlooked by patients who do not consider them "medications" to be disclosed.

High-dose multivitamin supplements

Some formulations combine several at-risk active ingredients (vitamin E, omega-3, plant extracts) without the patient identifying each component individually.

How to conduct the interview

Practical questions to integrate systematically

To be asked before any oral surgery procedure, particularly in polypharmacy elderly patients or before a bleeding-risk procedure.

Ask a specific, not generic, question — rather than "are you taking any medications?", ask explicitly: "do you take any dietary supplements, vitamins, or herbs, even occasionally?"

Cite concrete examples — mentioning garlic, ginkgo, St. John's Wort, omega-3, vitamin E helps the patient recall consumption they do not spontaneously associate with a "treatment."

Ask the patient to bring packaging or a list in cases of regular consumption of several products, for precise identification of active ingredients.

Systematically document in the chart — even in the absence of an identified interaction, this traceability protects both the patient and the practitioner.

Algerian context

A well-established traditional herbal medicine practice

The use of medicinal plants and traditional remedies is widespread among Algerian patients, often passed down within the family and perceived as complementary — or even alternative — to conventional pharmacological treatment. This culturally rooted practice reinforces the need for specific, non-judgmental questioning, since these products are even less likely to be spontaneously mentioned, as they are not perceived by the patient as belonging to the medical domain.

Ask without judgment, using relevant local examplesAdapt the examples cited during questioning to herbs and traditional practices commonly used locally, alongside international examples (garlic, ginkgo). An open, respectful question ("do you use any herbs or traditional preparations for your health?") often gathers more information than a question focused solely on "medications" in the Western sense of the term.

Availability of supplements

The market for herbal dietary supplements is growing in Algeria as elsewhere, with increasing availability in pharmacies and drugstores of standardized products (ginkgo, ginseng, turmeric) alongside informal traditional preparations — both channels deserve exploration during the medical history.

FAQ — Common Clinical Questions

For a simple extraction with low bleeding risk, continuing ginkgo is generally acceptable while applying the standard local hemostasis protocol, in the same way a conventional antiplatelet agent is managed for this type of procedure. Vigilance should be heightened if the patient is also taking a conventional anticoagulant or antiplatelet drug, or if the planned procedure is more invasive.

Antibiotics commonly used in dentistry (amoxicillin, clindamycin, spiramycin) have no major documented interaction with St. John's Wort via the CYP3A4/P-gp pathway. Vigilance should focus mainly on the patient's other medications (oral contraception, any cardiovascular treatment) rather than the antibiotic itself — but identifying St. John's Wort use should prompt a review of the entire current treatment regimen, not just the day's dental prescription.

No, it depends on the bleeding risk of the procedure and the specific product consumed. For low-risk procedures, continuation with reinforced local hemostasis is the approach consistent with the management of other antithrombotics. Discontinuation for 1 to 2 weeks is only warranted for high bleeding-risk procedures, and preferably in consultation with the treating physician if the supplement addresses a specific therapeutic indication (rather than a simple consumption habit).

Ginseng can lower blood glucose, which is relevant in cases of preoperative fasting or a prolonged procedure — inform the patient to monitor their blood glucose more closely around the intervention and to report any signs of hypoglycemia. This information adds to the usual management of the diabetic patient in the dental office, without radically altering the standard protocol.

Adopt a factual, non-judgmental tone, clearly explaining the clinical purpose of the question: "certain herbs or supplements can interact with anesthesia or increase bleeding risk, I'm asking for your safety, not to judge your choices." This approach, consistent with the recommended welcoming posture for other sensitive topics (see the article on opioid substitution treatment), encourages a more complete and honest disclosure.

Certain natural products present a low probability of drug interaction, with some caveats: this is the case notably for cranberry, milk thistle, saw palmetto, or valerian at usual doses (outside a sedation context, see Section 04). This distinction does not exempt the practitioner from systematic questioning, but it can help reassure a patient about certain specific products once identified and assessed.

References

1. Cummings KC, et al. Preoperative Management of Surgical Patients Using Dietary Supplements: Society for Perioperative Assessment and Quality Improvement (SPAQI) Consensus Statement. Mayo Clinic Proceedings. 2021;96(5):1342-1355. 2021

2. Dietary supplements and bleeding — systematic review of the bleeding risk of garlic, ginkgo, hawthorn, and other supplements. PMC. systematic review

3. Wang CZ, Moss J, Yuan CS. Commonly Used Dietary Supplements on Coagulation Function during Surgery. Medicines. 2015;2(3):157-185. review

4. Use of herbal medication in the perioperative period: Potential adverse drug interactions. ScienceDirect. 2024 — ASA/AANA recommendations on discontinuation timing. 2024

5. Journal of Dental Hygiene. Herbal supplements and dental treatment — recommendations specific to dental practice, 2-week discontinuation period. Vol. 81, No. 3, 2007. reference

6. Prevention Watch, Montreal Heart Institute. Interactions between natural products and medications — St. John's Wort, ginkgo, classification by risk level. reference

7. French National Academy of Pharmacy. Dietary supplements containing herbs — report on documented drug interactions. 2019. report

8. American College of Surgeons (ACS). Medication and Surgery: Before Your Operation — management of herbal supplements in the perioperative period, according to procedure risk. reference

9. PARC Preoperative Medication Guidelines, Stanford Medicine. Herbal supplements and anesthesia — effects on coagulation and anesthesia by product. reference

10. Pentel P, et al. Interactions between medications and preparations containing St. John's Wort, ginseng, ginkgo, garlic, kava, and valerian — synthesis cited by the Academy of Pharmacy. review

11. Public medicines database. Drug interactions of herbs and supplements — SmPCs and information sheets. reference

12. UT Southwestern Medical Center. Supplements and medications to pause before surgery — practical patient summary. reference

13. PharmNet-DZ. Herbal dietary supplements — availability and regulatory status in Algeria. local reference