Drug & supplement interaction

Calanus Oil + Guanabenz Acetate

Guanabenz Acetate brand name: Wytensin.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Calanus Oil and Guanabenz Acetate 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

Calanus Oil and Guanabenz Acetate

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 Guanabenz Acetate and Calanus Oil 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 Calanus Oil at all — not against Guanabenz Acetate, 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.

Calanus Oil safety at a glance

Calanus Oil overall Use caution Generally well tolerated in early studies, but long-term safety data in people are limited.
Pregnancy Avoid There is not enough safety information, so it is best to avoid during pregnancy.
Breastfeeding Avoid Safety during breastfeeding has not been established, so avoid unless your doctor advises otherwise.

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

Still wondering about combining Guanabenz Acetate and Calanus Oil? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

What Calanus Oil Itself Has Been Linked To

This is not an interaction — nothing below involves Guanabenz Acetate. It is the side-effect record for Calanus Oil on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Calanus Oil, this list is the first place to look.

  • A skin rash Additional detail

    “Calanus oil seems to be well tolerated. In one safety study, taking calanus oil for 12 months was reported to cause a higher rate of mild atopic dermatitis (eczema) when compared with placebo.”

    Calanus Oil · Natural Medicines adverse-effect record, reported in dermatitis.

    3 sources cited
    1. 97880. Cook CM, Larsen TS, Derrig LD, Kelly KM, Tande KS. Wax ester rich oil from the marine crustacean, Calanus finmarchicus, is a bioavailable source of EPA and DHA for human consumption. Lipids. 2016;51(10):1137-1144.
    2. 97881. Tande KS, Vo TD, Lynch BS. Clinical safety evaluation of marine oil derived from Calanus finmarchicus. Regul Toxicol Pharmacol. 2016;80:25-31. PubMed
    3. 105408. Dadová K, Petr M, Steffl M, et al. Effect of calanus oil supplementation and 16 week exercise program on selected fitness parameters in older women. Nutrients. 2020 Feb 14;12(2):481. PubMed

    “Orally, calanus oil is associated with more reports of mild atopic dermatitis (eczema) over a 12-month period when compared with placebo.”

    Calanus Oil · Natural Medicines adverse-effect record, reported in dermatitis.

    1 source cited
    1. 97881. Tande KS, Vo TD, Lynch BS. Clinical safety evaluation of marine oil derived from Calanus finmarchicus. Regul Toxicol Pharmacol. 2016;80:25-31. PubMed

Everything above comes from the Natural Medicines adverse-effect record for Calanus Oil — expand a row for the licensed statement it rests on. We haven’t matched Guanabenz Acetate to its FDA label in our system yet, so we can’t compare its own side-effect list here — the leaflet that comes with your prescription is the authoritative list for Guanabenz Acetate.

Everything else you take

See Every Supplement That Interacts With Guanabenz Acetate

This page covers Calanus Oil only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Guanabenz Acetate page lists 137 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Tyramine (major) and Adrafinil (moderate).

By severity: 4 major · 112 moderate · 21 minor.

From our pharmacist’s overview on the Guanabenz Acetate page

“Guanabenz acetate (Wytensin) is an older blood pressure medicine, and the 137 supplements on file call for genuine vigilance, beginning with the four rated major. Two are toxic plants that can strain the heart or swing pressure hard, one is tyramine, found in aged cheeses and cured meats, which fights the drug's effect, and one is acti…”

Reviewed by 2 · Jul 18, 2026

Open the Guanabenz Acetate interaction page

How much people look this up

Where Calanus Oil and Guanabenz Acetate 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 Calanus Oil
Steady interest

#1,257 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Guanabenz Acetate
Steady interest

#2,006 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 Calanus Oil reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Calanus Oil and Guanabenz Acetate 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 Calanus Oil

What is Calanus Oil?

  • Heart and metabolic health
  • Source of omega-3 fatty acids
  • Anti-inflammatory support
  • General wellness
  • Exercise and weight management

Calanus oil is a marine omega-3 oil made from a small Arctic zooplankton (Calanus finmarchicus). It is rich in omega-3 fatty acids bound in a unique 'wax ester' form, and early research suggests possible benefits for metabolic and heart health, but the evidence is still preliminary. Talk with your pharmacist or doctor before using it, especially if you have a seafood allergy or are pregnant.

Calanus finmarchicus · Calanidae · Oil extracted from the whole copepod (a tiny marine zooplankton) · Softgel capsules, oil

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

Calanus Oil: dosing

There is no official, standardized dose of calanus oil. Studies have used a fairly small daily amount, often just a gram or two per day, but products and concentrations vary.The best approach is to follow the dose printed on the product label and not exceed it.

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

Read the full Calanus Oil monograph & all interactions
Medication

About Guanabenz

What Is Guanabenz Used For?

Brand name: Wytensin

  • Guanabenz is used to treat high blood pressure. It is in a class of medications called centrally acting alpha2A-adrenergic receptor agonists. Guanabenz works by decreasing your heart rate and relaxing the blood vessels so that blood can flow more easily through the body.

  • High blood pressure is a common condition and when not treated, can cause damage to the brain, heart, blood vessels, kidneys and other parts of the body. Damage to these organs may cause heart disease, a heart attack, heart failure, stroke, kidney failure, loss of vision, and other problems. In addition to taking medication, making lifestyle changes will also help to control your blood pressure. These changes include eating a diet that is low in fat and salt, maintaining a healthy weight, exercising at least 30 minutes most days, not smoking, and using alcohol in moderation.

See full Guanabenz drug information
Keep checking

Other Drugs & Calanus Oil

Browse every other medication we’ve checked against Calanus Oil — 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
No interaction 2,829 drugs checked — show the list
Evidence & sources

Calanus Oil References

The 3 references that drive our Calanus Oil 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. Cook CM, Larsen TS, Derrig LD, Kelly KM, Tande KS. Wax ester rich oil from the marine crustacean, Calanus finmarchicus, is a bioavailable source of EPA and DHA for human consumption. Lipids. 2016;51(10):1137-1144.
  2. Tande KS, Vo TD, Lynch BS. Clinical safety evaluation of marine oil derived from Calanus finmarchicus. Regul Toxicol Pharmacol. 2016;80:25-31. PubMed
  3. Dadová K, Petr M, Steffl M, et al. Effect of calanus oil supplementation and 16 week exercise program on selected fitness parameters in older women. Nutrients. 2020 Feb 14;12(2):481. PubMed

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 Calanus Oil and Guanabenz Acetate Together: Common Questions

Is it safe to take Calanus Oil with Guanabenz Acetate?
We do not list a known interaction between Calanus Oil and Guanabenz Acetate. 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.
Does Guanabenz Acetate interact with any supplements?
Yes. Guanabenz Acetate has documented interactions with 137 supplements in our database — Calanus Oil is not one of them. The Guanabenz Acetate interaction page linked on this page lists every one, ranked by severity.

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

Still Have a Question About Guanabenz Acetate and Calanus Oil?

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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.