Probiotics has 2 documented interactions in Magellan’s curated dataset, covering Chemotherapy and cancer therapy, Antibiotics. Each entry below gives the mechanism as the cited reference states it, the direction the risk runs, how serious that reference treats it, and what to actually do about it — which is, in every case, a conversation with the clinician or pharmacist who manages the prescription rather than a decision you make alone.
What it is. Probiotics are live microorganisms that, when administered in adequate amounts, are intended to confer a health benefit on the host. Multi-strain formulations combine several bacterial species—most commonly strains of Lactobacillus and Bifidobacterium—delivered at doses measured in colony-forming units (CFU), with high-potency products supplying tens of billions of CFU per serving.
Where it sits on the evidence. Magellan grades the supplement itself as Moderate evidence. That grade is about whether it works, not about whether it is safe alongside your medication — the two questions are independent, and this page answers only the second.
Products this covers: Probiotic Multi-Strain (50B CFU).
How the risks cluster. Every entry on this page runs through the same mechanism — not a drug-level interaction — which means one conversation covers all of them.
Safety and efficacy are separate questions, and this page only answers the first. For the second, the study Magellan’s coverage of Probiotics rests on is:
“In older adults, multi-strain probiotic supplementation raised the anti-inflammatory cytokine IL-10 and short-chain fatty acids, although hs-CRP did not differ from placebo.”
A strong result does not make a supplement safe alongside your prescription, and a documented interaction does not mean the supplement does not work. Magellan grades those two things separately, and neither grade moves for a commission.
Magellan’s Medication Safety Check runs entirely on your device — type the medicines you take and it flags every documented interaction in this dataset. Nothing you type is sent anywhere.
Open the Medication Safety Check →People with severe illness or compromised immune systems, and critically ill hospitalized patients, are at greater risk of harmful effects from probiotics, including documented cases of severe or fatal infections; the FDA has specifically warned about this risk in premature infants given probiotics.
Medicines in this group include: Methotrexate (Trexall, Otrexup), Tamoxifen (Nolvadex), Cisplatin, Doxorubicin (Adriamycin), Vincristine (Oncovin), Bortezomib (Velcade), Cyclophosphamide (Cytoxan).
Probiotics are generally considered safe to take alongside antibiotics for most people, but extra caution is warranted in those who are very weak or have poorly functioning immune systems.
Medicines in this group include: Ciprofloxacin (Cipro), Levofloxacin (Levaquin), Moxifloxacin (Avelox), Doxycycline (Vibramycin), Minocycline (Minocin), Tetracycline (Sumycin), Cephalexin (Keflex), Cefdinir (Omnicef) and 3 more.
These are the warning signs that go with the medication classes on this page. They are general safety-netting, not a prediction that any supplement will cause them.
If something feels seriously wrong, do not wait for an appointment. Call 911 (US) or your local emergency number.
Severity describes the interaction as the cited reference frames it, not how a specific person will react. A “minor” entry in someone with kidney disease, on five other drugs, can matter more than a “major” one in someone on nothing else.
This is a curated set of interactions with citations — not an exhaustive pharmacology database. An interaction that is absent here has not been ruled out; it may simply not be documented in the references Magellan curates from. Supplements are also not batch-tested for identity or contamination the way prescription drugs are, so what is on the label is a claim rather than a guarantee. And most of these entries come from case reports and mechanistic work rather than randomized trials, which is exactly why the sensible response is a pharmacist review rather than either alarm or dismissal.
9 documented interactions across 9 supplements.
7 documented interactions across 6 supplements.
8 documented interactions · shares a drug class with Probiotics.
7 documented interactions · shares a drug class with Probiotics.
5 documented interactions · shares a drug class with Probiotics.
4 documented interactions · shares a drug class with Probiotics.
The mechanism and the research behind the compound itself.
The mechanism and the research behind the compound itself.
A–Z of every supplement and drug class in this dataset, plus how to read an interaction.
What the research actually shows, graded independently of affiliate commissions.
Not without checking with the prescriber or pharmacist first. Magellan's dataset grades this as a major interaction: People with severe illness or compromised immune systems, and critically ill hospitalized patients, are at greater risk of harmful effects from probiotics, including documented cases of severe or fatal infections; the FDA has specifically warned about this risk in premature infants given probiotics. (Source: Probiotics: Usefulness and Safety | NCCIH.)
2 interactions are documented in Magellan's curated dataset: 1 major, 1 minor. They cover Chemotherapy and cancer therapy, Antibiotics. Absence from this list is not proof of safety — it means no interaction is documented in the references we curate from.