Pine Bark Extract and medications.
Pine Bark Extract is in the Distil supplement database, evidence Grade B. The page below lists every medication we have explicitly assessed it against.
Pine bark extract, sold as Pycnogenol, is a procyanidin-rich extract taken at 100 to 200mg a day with Grade B evidence spread across several uses: erectile function, blood pressure and endothelial health, chronic venous insufficiency, cognition, osteoarthritis and skin. The breadth is a strength, but each indication rests on a handful of trials rather than one large body of proof. For erectile function it performs notably better combined with L-Arginine, with one trial restoring normal function in most men by three months. There is also paediatric ADHD data and a cardiometabolic meta-analysis. The interaction angle to watch is a mild antiplatelet effect at higher doses, putting it in the same low, reversible bracket as curcumin and garlic, so people on anticoagulants should be aware, and it can modulate immune function, which matters for anyone on immunosuppressants. It is generally very safe, with occasional headache or mild stomach upset. A flexible option, strongest for circulation and erectile support.
Below are the 15 documented pairs we have explicitly assessed for Pine Bark Extract: 15 amber. The pairs cluster around 4 mechanisms: Additive blood-pressure lowering, Additive anticoagulation, Additive antiplatelet effect, and Additive glucose lowering. Every call is cited to either a clinical reference (PMID) or the British National Formulary. Anything not listed here is either still to be assessed or beyond our database scope. The checker beneath surfaces assessments by medication, and the missing-item form at the bottom of the page routes any uncatalogued medication into our next curation pass.
Documented interactions
Additive blood-pressure lowering
Pine bark extract (pycnogenol) mildly lowers blood pressure, and amlodipine lowers it too. The combined effect tends to be a little larger than either alone. It is usually manageable, but watch for dizziness on standing in the first couple of weeks and tell your GP if symptoms appear.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Pine bark extract (pycnogenol) mildly lowers blood pressure, and bisoprolol lowers it too. The combined effect is small but real. Watch for dizziness on standing in the first couple of weeks and tell your GP if it happens.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Pine bark extract (pycnogenol) has a mild blood-pressure-lowering effect, and indapamide lowers blood pressure as well. The combined effect tends to be slightly larger. Watch for dizziness on standing in the first couple of weeks and tell your GP if symptoms appear.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Pine bark extract (pycnogenol) has a mild blood-pressure-lowering effect, and losartan lowers blood pressure as well. Together the combined effect tends to be slightly larger. It is usually manageable, but watch for dizziness on standing in the first couple of weeks and mention it to your GP if it happens.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Pine bark extract (pycnogenol) has a mild blood-pressure-lowering effect of its own, and ramipril lowers blood pressure too. Taken together the combined effect tends to be a little larger. It is usually manageable, but watch for dizziness on standing in the first couple of weeks and tell your GP if it happens.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Additive anticoagulation
Pine bark extract (pycnogenol) has a mild blood-thinning effect of its own, shown in people as reduced platelet stickiness, mainly in smokers. It has not been studied alongside acenocoumarol, so the size of any combined effect is unknown. If you take acenocoumarol, tell your anticoagulation clinic before starting pine bark extract and ask for an INR check a couple of weeks in.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Pine bark extract (pycnogenol) has a mild blood-thinning effect of its own, shown in people as reduced platelet stickiness. It has not been studied alongside warfarin, so the size of any combined effect is unknown. If you take warfarin, tell your anticoagulation clinic before starting pine bark extract and ask for an INR check a couple of weeks in.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Additive antiplatelet effect
Pine bark extract (pycnogenol) has a mild blood-thinning effect of its own, most clearly shown in smokers, that can add to aspirin's. For most people this is minor, but the combined effect can mean more bruising or bleeding, and it matters more before surgery. Stop high-dose pine bark extract at least a week before any planned procedure and tell your GP if you notice easy bruising.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Pine bark extract (pycnogenol) has a mild blood-thinning effect of its own, most clearly shown in smokers, that can add to clopidogrel's. For most people this is minor, but the combined effect can mean more bruising or bleeding. Stop high-dose pine bark extract at least a week before any planned surgery and tell your GP if you take the two together long-term or notice easy bruising.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Pine bark extract (pycnogenol) has a mild blood-thinning effect of its own, most clearly shown in smokers, that can add to ticagrelor's. The combined effect can mean more bruising or bleeding. Stop high-dose pine bark extract at least a week before any planned surgery and tell your GP if you take both together, especially if ticagrelor is combined with aspirin.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Additive glucose lowering
Pine bark extract (pycnogenol) may lower blood sugar a little on its own. Dapagliflozin also lowers blood sugar but rarely pushes it too low on its own, so the combination is generally manageable. Monitor your glucose when you start pine bark extract or change the dose.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Pine bark extract (pycnogenol) may lower blood sugar a little on its own. Gliclazide already lowers blood sugar and carries one of the higher risks of pushing it too low among the common diabetes tablets, so taking the two together may add up. If you take both, monitor your blood glucose, especially in the first few weeks, and your doctor may need to adjust the gliclazide dose.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Pine bark extract (pycnogenol) may lower blood sugar a little on its own, on top of the insulin you inject. This may increase the chance of glucose going too low. If you take pine bark extract with insulin, monitor your blood glucose closely, especially early on, and your doctor may need to reduce your insulin dose.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Pine bark extract (pycnogenol) may lower blood sugar a little on its own. Metformin also lowers blood sugar, so the two may add up. The combination is generally manageable because metformin on its own rarely causes low blood sugar, but monitor your glucose when you start pine bark extract or change the dose, and your doctor may adjust the metformin if needed.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Pine bark extract (pycnogenol) may lower blood sugar a little on its own. Sitagliptin also lowers blood sugar but rarely pushes it too low on its own, so the combination is generally manageable. Still, monitor your glucose when you start pine bark extract or change the dose.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
What this list does not say. Pairs not flagged here are not implicitly safe. They are either not yet in our database, or fall outside our inclusion scope. Use the checker below to surface any medication, and submit a missing item if you take something we have not catalogued.
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