Cranberry Extract (PAC-standardised) and medications.
Cranberry Extract (PAC-standardised) is in the Distil database but is not recommended: it is graded for none of the goals we score, so a Distil report never adds it to a stack. The page below lists every medication we have explicitly assessed it against.
Cranberry extract standardised for proanthocyanidins is taken to prevent recurrent urinary tract infections. The PACs stop P-fimbriated E. coli from sticking to the bladder wall, so the mechanism is anti-adhesive rather than antimicrobial. Evidence is Grade B for recurrent UTIs in women and for intervention-related UTIs after catheterisation, with around a quarter to a half reduction in recurrence depending on the group. Dose is the catch: you need at least 36mg of PACs a day, sustained for three to six months, and most over-the-counter capsules and gummies fall well below that and simply do not work. Choose a PAC-standardised tablet or capsule, not juice, which carries a heavy sugar load. Benefit was not shown in institutionalised elderly adults or in neuromuscular bladder dysfunction. On interactions, monitor INR if combined with warfarin, and avoid high-volume juice. Exclude it in pregnancy, where trials showed no benefit, and in anyone with a calcium oxalate kidney stone history, since cranberry raises urinary oxalate.
Below are the 2 documented pairs we have explicitly assessed for Cranberry Extract (PAC-standardised): 2 caution. The pairs cluster around 1 mechanism: Additive anticoagulation. 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
Last reviewed 14 June 2026. Each interaction below lists the evidence its assessment drew on: some rest on studies of the exact pair, others on mechanism evidence, where a citation may support one part of the reasoning rather than the exact combination. The evidence line on each entry says which.
Additive anticoagulation
Caution Does Cranberry Extract (PAC-standardised) interact with Acenocoumarol?
Cranberry can raise the effect of acenocoumarol, a blood thinner in the same family as warfarin, and push your INR up; with warfarin this was seen with large volumes of juice and, in a controlled trial, with capsules. The signal comes from the related drug warfarin rather than from acenocoumarol directly. If you take acenocoumarol, keep your cranberry intake steady rather than starting or stopping it suddenly, and tell your anticoagulant clinic so your INR can be watched.
Evidence: No direct study of this exact combination yet; the caution rests on a plausible mechanism or on reports involving a related medicine.
Reviewer-flagged: awaiting clinical-reviewer sign-off.
Caution Does Cranberry Extract (PAC-standardised) interact with Warfarin sodium?
Cranberry can push warfarin's blood-thinning effect higher. Most case reports involve large volumes of juice, but in a controlled trial cranberry capsules raised warfarin's effect too, so tell your GP whichever form you take and ask whether INR monitoring should be a little tighter for the first few weeks.
Evidence: Supported by human study data.
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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How the checker decides
Every result has a source
Each pair we have assessed is cited to a published study (PMID) or the British National Formulary, so you can read the source yourself.
Four kinds of answer
Severe, caution, no known interaction, and not yet assessed. A pair we have not assessed is never shown as clear.
- Severe
- Caution
- No known interaction
- Not yet assessed
Nothing in our data is not a clearance
When nothing in our data records a problem with a pair, the result says no known interaction at typical doses, which is not a clearance: your pharmacist or GP can check the pair against your full medical history.
A full supplement review, built around you, not a generic stack.
The free checker answers one interaction question at a time. A Distil report reviews the bigger picture: your goals, diet, medications, current supplements and any blood results you provide, then shows what appears worth keeping, changing, adding or leaving out.
- what your diet already covers, so you are not adding a capsule for something food is already handling
- which evidence-graded compounds are worth considering for your goals, and which were considered but left out
- what to keep, change or stop from what you already take, plus the order to introduce anything new
- how your medications and complete supplement stack fit together, with daily timing and a clear point for reassessment
The interaction check is one section of the full report. You also get the reasoning behind each recommendation and the evidence references used.
£49 until 30 June 2027 · £79 from 1 July 2027.
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