Drug & supplement interaction

Herb Robert + Cephalexin

Cephalexin brand names: Keflex, Keftab, Cephalex, Lexin.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 20, 2026
The bottom line No known interaction

We found no known interaction between Herb Robert and Cephalexin in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first.

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Interaction report

Herb Robert and Cephalexin

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Cephalexin and Herb Robert in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

Worth understanding: our licensed dataset holds no drug-interaction record for Herb Robert at all — not against Cephalexin, and not against any other medication we track. This verdict therefore rests on the absence of any recorded data, not on research that looked at this combination and found nothing. We cannot rule an interaction out.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Herb Robert safety at a glance

Herb Robert overall Use caution Generally used in small amounts traditionally, but human safety data are very limited.
Pregnancy Avoid Not enough safety information, so it is best avoided during pregnancy.
Breastfeeding Avoid No reliable safety data exist for nursing mothers, so avoid use.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Cephalexin and Herb Robert? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

What Herb Robert Itself Has Been Linked To

This is not an interaction — nothing below involves Cephalexin. It is the side-effect record for Herb Robert on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Herb Robert, this list is the first place to look. One entry is worth acting on rather than waiting out — marked below.

  • A severe skin reaction Worth acting on Additional detail

    “Topically, Herb Robert can cause contact dermatitis. There are at least two cases of known contact sensitization of elderly individuals to Herb Robert through gardening. One case resulted in an erythema multiforme-like eruption requiring treatment with steroids.”

    Herb Robert · Natural Medicines adverse-effect record, reported in dermatitis.

    2 sources cited
    1. 99144. Svendsen MT, Andersen KE, Thormann H, Paulsen E. Contact sensitization to Geranium robertianum L. in an amateur gardener. Contact Dermatitis. 2015;72(6):420-1.
    2. 99146. Badaoui A, Pecquet C, Fargeas C, Mahé E. Contact dermatitis caused by Geranium robertianum with erythema multiforme-like reaction. Contact Dermatitis. 2017;77(6):423-424.
  • A skin rash Additional detail

    “There is currently a limited amount of information on the adverse effects of Herb Robert. Topically, Herb Robert has been reported to cause allergic contact dermatitis.”

    Herb Robert · Natural Medicines adverse-effect record, reported in dermatitis.

    2 sources cited
    1. 99144. Svendsen MT, Andersen KE, Thormann H, Paulsen E. Contact sensitization to Geranium robertianum L. in an amateur gardener. Contact Dermatitis. 2015;72(6):420-1.
    2. 99146. Badaoui A, Pecquet C, Fargeas C, Mahé E. Contact dermatitis caused by Geranium robertianum with erythema multiforme-like reaction. Contact Dermatitis. 2017;77(6):423-424.

Everything above comes from the Natural Medicines adverse-effect record for Herb Robert — expand a row for the licensed statement it rests on. We read the ADVERSE REACTIONS section of Cephalexin’s FDA label too, and the two lists don’t meaningfully overlap — which is why no Cephalexin column appears here.

Overlapping uses

What Cephalexin Is Prescribed For, and What Herb Robert Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Cephalexin is a prescription medicine with approved uses on its FDA label. Herb Robert is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Cephalexin is prescribed for: Cephalexin treats bacterial infections caused by susceptible strains of bacteria. It is used for respiratory tract infections, ear infections (otitis media), skin and skin structure infections, bone infections, and genitourinary tract infections — including acute prostatitis. It works only against bacterial infections — not viruses like colds or flu. Your prescriber should use it only when a bacterial infection is confirmed or strongly suspected, to help prevent antibiotic resistance.

Herb Robert has been studied for:

  • Otitis media studied, not established Herb Robert has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Herb Robert for otitis media

    Clinical research of an herbal mixture containing the essential oils of Herb Robert, clove, and lavender shows that placing 3 drops in the ear every 12 hours for one week improves otitis media symptoms including pain, tenderness, itching, edema, and discharge when compared with baseline. These improvements are similar to those achieved with ciprofloxacin 0.3% otic drops.

    1 source cited
    1. 99145. Panahi Y, Akhavan A, Sahebkar A, et al. Investigation of the effectiveness of Syzygium aromaticum, Lavandula angustifolia and Geranium robertianum essential oils in the treatment of acute external otitis: a comparative trial with ciprofloxacin. J Microbi PubMed

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Cephalexin on your own; if you are taking Herb Robert for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

From our Q&A

Questions About Herb Robert or Cephalexin

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Herb Robert or Cephalexin, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Cephalexin

This page covers Herb Robert only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Cephalexin page lists 61 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Asarabacca (major), Siberian Cocklebur (major), African Wild Potato (moderate) and Aristolochia (moderate).

By severity: 3 major · 47 moderate · 11 minor.

From our pharmacist’s overview on the Cephalexin page

“Cephalexin (Keflex) is one of the most commonly prescribed oral antibiotics, usually for skin and urinary infections, and its supplement list warrants genuine care rather than a quick skim. Three of the 61 ingredients on file rate major.”

Reviewed by 2 · Jul 18, 2026

Open the Cephalexin interaction page

How much people look this up

Where Herb Robert and Cephalexin Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Herb Robert
Steady interest

#908 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Cephalexin
Top 5%

#139 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Herb Robert reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Herb Robert and Cephalexin records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Herb Robert

What is Herb Robert?

Herb Robert
  • Digestive upset
  • Wound and skin care
  • Sore throat and mouth irritation
  • Respiratory complaints
  • General 'detox' tonic

Herb Robert is a traditional European herb used for digestion, wounds, and minor inflammation, but there is very little human research to confirm it works for any condition. It is likely fine in small amounts as a tea for most healthy adults, but its safety has not been well studied. Talk to your pharmacist or doctor before using it, and avoid it during pregnancy and breastfeeding.

Geranium robertianum · Geraniaceae · Above-ground parts (leaves, stems, and flowers) · Tea, tincture, dried herb, capsules, fresh poultice

An interaction check asks whether these two react with each other — it does not ask whether Herb Robert is a good idea for someone in your situation. Here is what our Herb Robert record says about it on its own.

Herb Robert: dosing

There is no established, standardized dose for Herb Robert. Traditional use involved brewing a small amount of the dried herb as a tea or applying crushed fresh leaves to the skin, but these amounts were not measured in a consistent, science-based way.If you choose to use a commercial product, follow the directions on the label and do not exceed the recommended amount.

From our Herb Robert monograph — the full record covers uses, side effects and every documented interaction.

Read the full Herb Robert monograph & all interactions
Medication

About Cephalexin

What Is Cephalexin Used For?

Brand names: Keflex, Keftab, Cephalex, Lexin

Cephalexin treats bacterial infections caused by susceptible strains of bacteria. It is used for respiratory tract infections, ear infections (otitis media), skin and skin structure infections, bone infections, and genitourinary tract infections — including acute prostatitis.

It works only against bacterial infections — not viruses like colds or flu. Your prescriber should use it only when a bacterial infection is confirmed or strongly suspected, to help prevent antibiotic resistance.

Most-Reported Side Effects for Cephalexin

From FAERS, the FDA’s public side-effect reporting system (0 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Chronic kidney disease 2,157 reports
Renal failure 1,558 reports
Acute kidney injury 1,550 reports
Diarrhea 1,405 reports
Fatigue 1,303 reports
See full Cephalexin drug information
Keep checking

Other Drugs & Herb Robert

Browse every other medication we’ve checked against Herb Robert — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
0Moderate
0Minor
2,829No known interaction
2,829 No interaction
No interaction 2,829 drugs checked — show the list

We also checked Herb Robert against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,829 medications checked with no known interaction — see the full Herb Robert list.

See the full Herb Robert interactions page
See every supplement checked against Cephalexin, ranked by severity
Evidence & sources

Herb Robert References

The 3 references that drive our Herb Robert monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Svendsen MT, Andersen KE, Thormann H, Paulsen E. Contact sensitization to Geranium robertianum L. in an amateur gardener. Contact Dermatitis. 2015;72(6):420-1.
  2. Panahi Y, Akhavan A, Sahebkar A, et al. Investigation of the effectiveness of Syzygium aromaticum, Lavandula angustifolia and Geranium robertianum essential oils in the treatment of acute external otitis: a comparative trial with ciprofloxacin. J Microbi PubMed
  3. Badaoui A, Pecquet C, Fargeas C, Mahé E. Contact dermatitis caused by Geranium robertianum with erythema multiforme-like reaction. Contact Dermatitis. 2017;77(6):423-424.

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Herb Robert and Cephalexin Together: Common Questions

Is it safe to take Herb Robert with Cephalexin?
We do not list a known interaction between Herb Robert and Cephalexin. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Are Herb Robert and Cephalexin used for the same thing?
They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Herb Robert in each. That is a conversation for your prescriber, especially if Cephalexin is being adjusted to a target.
Does Cephalexin interact with any supplements?
Yes. Cephalexin has documented interactions with 61 supplements in our database — Herb Robert is not one of them. The Cephalexin interaction page linked on this page lists every one, ranked by severity.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Where next

Keep Exploring

Herb Robert monograph Uses, safety profile, and every drug interaction in one place Cephalexin drug information The full plain-English guide to this medication Cephalexin supplement interactions Every supplement checked against Cephalexin, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 3 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Cephalexin and Herb Robert?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.