Nasturtium + Doxycyline

At least one FDA label for a product containing Doxycyline says to take it on an empty stomach. Most supplements — Nasturtium included — are taken with a meal, so the easy mistake is swallowing both together at breakfast. Where that rule applies, keep Doxycyline on its own and move Nasturtium to a meal later in the day.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Doxycyline products can carry different directions, and extended-release forms often differ from immediate-release ones. The label we read is quoted below — check the directions on your own box or bottle, or ask your pharmacist, for how to take the exact product you were given.

A food rule is not an interaction — it is about how much of the medicine you absorb. The directions that came with your own product, and your pharmacist, outrank anything on this page.

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

Doxycyline is prescribed for: Doxycycline belongs to the tetracycline family of antibiotics. It's prescribed for many types of bacterial infections, including respiratory tract infections, sexually transmitted infections (STIs), tick-borne illnesses like Rocky Mountain spotted fever, and eye infections. It's also used to help prevent malaria and, in some cases, as a helper treatment for severe acne. In situations where penicillin-type antibiotics can't be used — due to allergy, for example — doxycycline can step in as an alternative.

Nasturtium has been studied for:

• Respiratory tract infections studied, not established Nasturtium has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

  Nasturtium for respiratory tract infections

  Preliminary clinical research in patients with a history of recurrent respiratory tract infections (RTIs) shows that taking a specific combination product (Angocin Anti-Infekt N, Repha GmbH) containing a total of 320-400 mg horseradish root and 800-1000 mg nasturtium daily for 12 weeks modestly decreases the rate of new RTIs when compared with placebo.

  1 source cited

  1. 96309. Fintelmann V, Albrecht U, Schmitz G, Schnitker J. Efficacy and safety of a combination herbal medicinal product containing Tropaeoli majoris herba and Armoraciae rusticanae radix for the prophylactic treatment of patients with respiratory tract diseases:

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 Doxycyline on your own; if you are taking Nasturtium for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Nasturtium or Doxycyline, 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:

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

This page covers Nasturtium only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Doxycyline page lists 149 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Asarabacca (major), Beer (major), Oleander (major), Siberian Cocklebur (major) and St. John's Wort (major).

By severity: 6 major · 132 moderate · 11 minor.

Open the Doxycyline interaction page ›

We hold 3 real supplement products containing Nasturtium, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Nasturtium. Even though Nasturtium itself has no known interaction with Doxycyline, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

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.

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.

Natural Medicines records Doxycyline as a medicine that can lower these. This is not an interaction with Nasturtium — it is a separate effect of the medicine, and it is a reason some people are advised to supplement rather than to avoid one:

• BIOTIN›
• FOLIC ACID›
• RIBOFLAVIN›
• THIAMINE›
• VITAMIN B12›
• VITAMIN B6›
• VITAMIN K›

Read the full Doxycyline nutrient depletion report ›

Depletion records come from the licensed Natural Medicines database. Do not start a supplement on the strength of this page — ask your pharmacist or doctor whether it applies to you.