Drug & supplement interaction

Calanus Oil + Niraparib Tosylate

Niraparib Tosylate brand name: Zejula.

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 Calanus Oil and Niraparib Tosylate 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. Additionally, although there is no interaction, the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Calanus Oil and Niraparib Tosylate

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 Niraparib Tosylate 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 Niraparib Tosylate, 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 Niraparib Tosylate and Calanus Oil? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests Calanus Oil and Niraparib Tosylate May Share a Side Effect

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do.

  • A skin rash Additional detail

    Calanus Oil

    “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

    Niraparib Tosylate

    Listed in the ADVERSE REACTIONS section of the FDA label for Niraparib Tosylate. Read the label on DailyMed ›

Effects for Niraparib Tosylate come from the ADVERSE REACTIONS section of its FDA label; effects for Calanus Oil come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 51 voluntary FDA FAERS reports for Niraparib Tosylate that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Everything else you take

See Every Supplement That Interacts With Niraparib Tosylate

This page covers Calanus Oil only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Niraparib Tosylate page lists 54 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), St. John's Wort (major), Bitter Melon (moderate), Black Pepper (moderate) and Bulbine Natalensis (moderate).

By severity: 2 major · 35 moderate · 17 minor.

From our pharmacist’s overview on the Niraparib Tosylate page

“Activated charcoal, popular for bloating and so-called detox routines, can trap niraparib (Zejula) in the gut before it absorbs, and St. John's wort can drive levels of the drug down another way.”

Reviewed by 2 · Jul 18, 2026

Open the Niraparib Tosylate interaction page

How much people look this up

Where Calanus Oil and Niraparib Tosylate 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

#1,236 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Niraparib Tosylate
Steady interest

#2,057 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 Niraparib Tosylate 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 Niraparib

What Is Niraparib Used For?

Brand name: Zejula

Zejula is used as maintenance therapy — meaning it is taken after chemotherapy to help keep the cancer from coming back — for adults with advanced epithelial ovarian, fallopian tube, or primary peritoneal cancer. For first-line maintenance, Zejula is approved for patients whose cancer is HRD-positive (has certain DNA-repair defects, including BRCA mutations or genomic instability) and who have responded to their first round of platinum-based chemotherapy.

Zejula is also approved for maintenance treatment in adults with recurrent ovarian, fallopian tube, or primary peritoneal cancer that carries a germline BRCA mutation (an inherited change in the BRCA gene), when the cancer has responded to platinum-based chemotherapy. In both cases, a companion diagnostic test is required to confirm eligibility before starting Zejula.

Most-Reported Side Effects for Niraparib Tosylate

From FAERS, the FDA’s public side-effect reporting system (51 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Constipation 4 reports
Decreased appetite 4 reports
Fatigue 4 reports
Nausea 4 reports
Prostatic specific antigen increased 4 reports
See full Niraparib 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
2,829 No interaction
No interaction 2,829 drugs checked — show the list

We also checked Calanus Oil 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 Calanus Oil list.

See the full Calanus Oil interactions page
See every supplement checked against Niraparib Tosylate, ranked by severity
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 Niraparib Tosylate Together: Common Questions

Is it safe to take Calanus Oil with Niraparib Tosylate?
We do not list a known interaction between Calanus Oil and Niraparib Tosylate. 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.
Do Calanus Oil and Niraparib Tosylate have any of the same side effects?
Yes — our sources link each of them separately to one of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Does Niraparib Tosylate interact with any supplements?
Yes. Niraparib Tosylate has documented interactions with 54 supplements in our database — Calanus Oil is not one of them. The Niraparib Tosylate 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

Calanus Oil monograph Uses, safety profile, and every drug interaction in one place Niraparib drug information The full plain-English guide to this medication Niraparib Tosylate supplement interactions Every supplement checked against Niraparib Tosylate, 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 Niraparib Tosylate 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.