Over-the-Counter Supplements That Can Cause Low Platelet Count
Yes, several over-the-counter supplements can cause thrombocytopenia or affect platelet function, though direct platelet count reduction is less common than platelet dysfunction leading to bleeding risk.
Supplements with Antiplatelet Effects (Not True Thrombocytopenia)
Most OTC supplements affect platelet function rather than causing true low platelet counts. These include:
High-Risk Supplements for Platelet Dysfunction
Ginkgo biloba: Contains ginkgolide B which displaces platelet-activating factor from binding sites, decreasing coagulation 1. Should be held for 2 weeks before surgery 1.
Ginger: Five of 20 constituents shown to inhibit platelet aggregation in vitro, with case reports of elevated INR and epistaxis 1. Laboratory evidence shows inhibition of thromboxane synthetase with decreased platelet aggregation 1.
Garlic: Inhibition of platelet function documented in case reports, particularly at doses of 12g daily when combined with SSRIs 1. Case series report spontaneous bleeding events with doses ranging from 75-600 mg/day for 1 week to 2 years 1.
Flaxseed oil: Decreased platelet aggregation in healthy men receiving 40 g/day for 23 days and has been associated with increased bleeding 1.
Green tea extract: Active ingredient EGCG inhibits platelet aggregation and decreases binding of fibrinogen to platelet surface GPIIb/IIIa 1. However, the 2021 Mayo Clinic guidelines note it may be continued until surgery despite bleeding risk 1.
Moderate-Risk Supplements
Fenugreek: Aqueous extracts inhibit coagulation process in vitro and significantly prolong prothrombin time 1.
Turmeric/Curcumin: Anti-inflammatory and antiplatelet effects with prolongation of activated partial thromboplastin time 1.
Saw palmetto: Conflicting data on bleeding risk exists 1.
Fish oil/Omega-3 fatty acids: While shown in vitro to inhibit platelet-to-platelet adhesion and platelet-stimulated thrombin generation, a large placebo-controlled trial showed no increase in perioperative bleeding 1. The 2021 Mayo Clinic guidelines recommend these be continued 1.
True Thrombocytopenia from Supplements
Direct platelet count reduction from OTC supplements is rare and poorly documented in the literature. The evidence focuses primarily on platelet dysfunction rather than quantitative thrombocytopenia 2, 3.
Clinical Implications
When to Suspect Supplement-Related Platelet Issues
Platelet dysfunction (normal count but increased bleeding): Consider if patient reports easy bruising, prolonged bleeding from cuts, petechiae, or purpura while taking supplements listed above 4.
True thrombocytopenia (platelet count <150,000/μL): First exclude pseudothrombocytopenia by repeating count in heparin or sodium citrate tube 4. If confirmed, drug-induced thrombocytopenia from prescription medications is far more common than supplement-induced 4, 5.
Perioperative Management
All supplements with antiplatelet effects should ideally be discontinued 1-2 weeks before elective surgery 1. This recommendation comes from the American Society of Anesthesiology and multiple surgical societies 1.
In one survey, 19% of surgical patients were taking supplements with potential coagulation effects, and 12.5% of these patients had actual intraoperative hemorrhage 1.
Chondroitin and glucosamine may be held for only 48 hours due to rapid metabolism 1.
Common Pitfalls
Patients often don't report supplement use: Specifically ask about ginger tea, garlic supplements, fish oil, ginkgo, and herbal products 2, 6.
Assuming "natural" means safe: Approximately 180 dietary supplements have potential to interact with warfarin, and more than 120 may interact with antiplatelet drugs 2.
Focusing only on prescription medications: When evaluating unexplained bleeding or preparing for procedures, always obtain a complete supplement history 3, 6.