Supplements and Nadolol.
Nadolol, sold under the brand name Corgard, is a beta-blocker: it reduces heart rate and cardiac output by antagonising beta-adrenergic receptors.
Nadolol is a beta-blocker. The class reduces heart rate and cardiac output. Depending on receptor selectivity, it can also carry bronchospasm risk in patients with asthma. Cardiac-selective agents (bisoprolol, atenolol, nebivolol) carry lower bronchospasm risk than the agents that block both receptors (propranolol, carvedilol). The supplement surface is mostly quiet. The class is not strongly CYP metabolised in most cases, so the CYP interactions seen with statins and SSRIs do not apply here. Additive bradycardia from CoQ10 is small and clinically minor. Additive hypotension from beetroot, hibiscus, garlic, and magnesium at higher doses can stack on top. The signal to watch in the early weeks of any agent in this class is a resting heart rate below 50 or symptomatic dizziness on standing. Both warrant a dose review with the GP.
Below are the 1 documented pair we have explicitly assessed against Nadolol in the Distil database: 1 amber. The pairs cluster around 1 mechanism: OATP transporter inhibition (reduced absorption). Every call is cited to either a clinical reference (PMID) or the British National Formulary. Anything not on this list is either still to be assessed or beyond our database scope. The checker beneath surfaces assessments by supplement, and the missing-item form at the bottom of the page routes any uncatalogued supplement into our next curation pass.
Documented interactions
OATP transporter inhibition (reduced absorption)
Green tea can sharply cut how much nadolol your body absorbs, which can leave the beta-blocker working much less well at controlling your blood pressure or heart rate. In a study in healthy people, drinking green tea reduced nadolol levels in the blood by about 85 percent and blunted its blood-pressure effect. If you take nadolol, it is best not to take it with green tea or green tea extract: keep them several hours apart, keep your intake steady rather than starting or stopping suddenly, and tell your prescriber so your readings can be checked.
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 (food-supplement interactions only; for drug-drug interactions, the BNF is authoritative). Use the checker below to surface any supplement, and submit a missing item if you take something we have not catalogued.
How we grade severity, choose what's in scope, and what we exclude.
Every call on this page is reasoned. We publish the full rubric for severity tiers, the medication inclusion logic, the evidence grades we accept, and what we deliberately leave out. About three thousand words. Worth reading once if you use this tool more than occasionally.
Read the full methodologyWant this reasoning across everything you take?
This page checks the pairs you enter. A personalised Distil report applies the same graded, cited reasoning to your whole stack: your goals, conditions, medications, diet, and the compounds worth adding or dropping. The interactions check is one section of it. You can read a real one in full before you decide.
See a real sample reportSomething missing?
If a supplement or medication you take isn't in our autocomplete, tell us. We go through what people flag every week and add what's missing.