Table 4.
Common supplement interactions.
| Supplement | Potential Interactions | Description of Interaction | Precautionary Measures |
|---|---|---|---|
| St. John’s Wort | Medications: Antidepressants (SSRIs and MAOIs), birth control pills, blood thinners (warfarin), immunosuppressants, anti-seizure drugs | Can decrease the effectiveness of medications (e.g., antidepressants and birth control) or increase the risk of serotonin syndrome and bleeding when combined with SSRIs. | Avoidance of St. John’s wort is recommended when taking certain medications, and consultation with a healthcare provider is essential before starting its use. |
| Vitamin K | Medications: Blood thinners (e.g., warfarin) | This can reduce the effectiveness of blood thinners by promoting clotting; this could lead to dangerous clotting conditions. | Consistent intake of vitamin K is advised, with monitoring of INR levels if on warfarin; consultation with a healthcare provider is recommended. |
| Calcium | Medications: Antibiotics (e.g., tetracyclines and quinolones) and thyroid medications (e.g., levothyroxine) | Calcium can bind to certain antibiotics or thyroid medications in the digestive tract, reducing their absorption and effectiveness. | Calcium supplementation should be timed differently from these medications, ensuring a 2–4-h separation. |
| Iron | Medications: Antibiotics (e.g., tetracyclines and fluoroquinolones), antacids, thyroid medications (levothyroxine) | Iron can decrease the absorption of certain medications and be affected by antacids, reducing its own absorption. | Separation of iron supplements from these medications by at least 2 h is advised, and high-dose iron supplementation should be avoided without medical guidance. |
| Omega-3 fatty acids | Medications: Blood thinners (e.g., warfarin and aspirin) and non-steroidal anti-inflammatory drugs (NSAIDs) | High doses of omega-3s can increase bleeding risk, especially when combined with blood thinners or NSAIDs. | Limitation of omega-3 supplement intake to 1000 mg/day is advised without medical consultation; discussion with a healthcare provider is recommended. |
| Magnesium | Medications: Antibiotics (e.g., tetracyclines and quinolones), diuretics, muscle relaxants, osteoporosis medications (bisphosphonates) | This can reduce the absorption and effectiveness of certain antibiotics and osteoporosis medications; it may potentiate the effects of muscle relaxants and diuretics. | Separation of magnesium supplementation from these medications by several hours is recommended, and verification of potential interactions with a pharmacist is advised. |
| Ginseng | Medications: Blood pressure medications, anticoagulants, stimulants, diabetes medications | This can affect blood pressure levels, increase the risk of bleeding, or interact with diabetes medications to affect blood sugar levels. | Avoidance of these medications unless supervised by a healthcare provider is recommended, with monitoring of blood pressure and glucose levels. |
| Vitamin D | Medications: Steroids (e.g., prednisone), weight-loss drugs (e.g., orlistat), cholesterol-lowering drugs (e.g., cholestyramine). | Some medications can reduce vitamin D absorption or increase its metabolism, reducing its effectiveness; high doses can lead to hypercalcemia. | Regular monitoring of vitamin D levels is recommended when on these medications, and avoidance of high-dose supplementation without a doctor’s advice is advised. |
| Ginkgo Biloba | Medications: Blood thinners (e.g., warfarin and aspirin), anticonvulsants, antidepressants, NSAIDs, diabetes medications | Increases the risk of bleeding when combined with blood thinners; can affect blood sugar levels or cause seizures with anticonvulsants. | Cautious use of these medications is recommended; consultation with a healthcare provider is essential, especially when on blood thinners. |
| Zinc | Medications: Antibiotics (e.g., tetracyclines and quinolones), diuretics, immune-suppressing drugs (e.g., cyclosporine) | Zinc can interfere with the absorption of certain antibiotics and increase the risk of side effects with immune-suppressing drugs. | Zinc supplementation should be taken separately from these medications, and guidance from a healthcare provider is advised |
| Melatonin | Medications: Sedatives (e.g., benzodiazepines), blood pressure medications, anticoagulants, immunosuppressants, contraceptives | It can potentiate the effects of sedatives, affect blood pressure levels, increase bleeding risk, or interfere with the efficacy of immunosuppressants and contraceptives. | Cautious use of these medications is advised, with a discussion about potential interactions with a healthcare provider. |
| Coenzyme Q10 (CoQ10) | Medications: Blood pressure medications, chemotherapy drugs, blood thinners (e.g., warfarin). | May reduce the effectiveness of blood thinners, lower blood pressure excessively, or interfere with chemotherapy drugs’ effectiveness. | Monitoring blood pressure and INR levels is essential, and consultation with a healthcare provider is recommended before using CoQ10 when on these medications. |