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Do Patients With Fish or Shellfish Allergy Tolerate the Consumption of Fish Oil Supplements? A Clinical Study

Tolererer Fiske- og Skaldyrsallergikere Fiskeolietilskud? Et Klinisk Studie

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05677074
Enrollment
9
Registered
2023-01-10
Start date
2023-01-01
Completion date
2023-04-24
Last updated
2023-04-25

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Food Hypersensitivity

Brief summary

The purpose of this clinical study is to test whether patients with fish or shellfish allergy can ingest different types of fish oil supplements without having an allergic reaction. To achieve this, the recruited participants will be asked to: * provide a blood sample (used for Basophil Histamine Release Assay) * undergo a skin-prick-test * partake in multiple oral provocations These three tests will indicate the likelihood that the participants can consume fish oil supplements without adverse allergic reactions (See the detailed description for an explanation of the tests). The investigators will test the participants tolerance for three different types fish oil supplements: Fish oil, Cod liver oil, and krill oil.

Detailed description

The Basophil Histamine Release Assay is a test that indicates whether or not the immune cells of the participant reacts when it comes into contact with the fish oils. The skin-prick-test involves the participants having their skin exposed to the fish oils. This is done by first exposing a tiny needle to the given fish oil, and then pricking the needle into the skin on the forearm of the participant. In this way, the immune cells of the skin is exposed to the fish oils. If an allergic reaction occurs, the pricked skin will swell and turn reddish. During the oral provocation, the participant is asked to ingest small, but increasing, doses of the fish oils over a period of 2 hours. The provocation will end when either an allergic reaction occurs or the participant has ingested a total dose of 5 mL fish oil.

Interventions

DIETARY_SUPPLEMENTFish oil

The tolerance of fish oil is tested using three methods: skin-prick-test, Basophil Histamine Release Assay, and oral provocation.

DIETARY_SUPPLEMENTCod oil

The tolerance of cod oil is tested using three methods: skin-prick-test, Basophil Histamine Release Assay, and oral provocation.

DIETARY_SUPPLEMENTKrill oil

The tolerance of krill oil is tested using two methods: skin-prick-test and Basophil Histamine Release Assay. (We were unable to acquire enough liquid krill oil to perform oral provocation with this supplement).

Sponsors

University Hospital, Gentofte, Copenhagen
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Adult (≥18 years old) * Legally competent * Understands Danish

Exclusion criteria

* Current use of antihistamine, immunosuppressants, and/or anti-IgE-treatment that cannot be safely terminated during the study period * The presence of severe diseases such as: Cardiovascular disease, asthma, cancer, liver disease, kidney disease, hematological diseases, neurological diseases, dementia, immunological diseases, and endocrine diseases * Chronic urticaria * Severe atopic eczema * Pregnancy and/or breastfeeding * Participation in another clinical study the previous three months * Known excessive use of alcohol and/or substance abuse

Design outcomes

Primary

MeasureTime frameDescription
Allergic reactions during fish oil provocation.At 2 hours after the provocation or at the end of the provocation if terminated early (in case of allergic reaction).Presence of objective allergic symptoms (i.e. hives, redness, respiratory difficulties, and changes in blood pressure) during and two hours after the oral provocation.
Allergic reactions during cod oil provocation.At 2 hours after the provocation or at the end of the provocation if terminated early (in case of allergic reaction).Presence of objective allergic symptoms (i.e. hives, redness, respiratory difficulties, and changes in blood pressure) during and two hours after the oral provocation.
Allergic reactions during krill oil provocation.At 2 hours after the provocation or at the end of the provocation if terminated early (in case of allergic reaction).Presence of objective allergic symptoms (i.e. hives, redness, respiratory difficulties, and changes in blood pressure) during and two hours after the oral provocation.

Secondary

MeasureTime frameDescription
Blood pressure during oral provocationsChange in blood pressure from baseline in case of allergic reactionBlood pressure (mmHg) is measured to detect possible changes from baseline,indicating the severity of an allergic reaction
Skin-prick-test15 minutes after the skin-prick-test has been administered.The size of the hives are measured, if the diameter is \>3 mm it is considered a positive result, if the negative and positive control are negative and positive, respectively
Peak flow during oral provocationsChange in blood pressure from baseline in case of allergic reactionPeak flow (liters pr. minute) is measured to detect possible changes from baseline, indicating the severity of an allergic reaction
Pulse during oral provocationsChange in blood pressure from baseline in case of allergic reactionPulse (beats pr. min) is measured to detect possible changes from baseline, indicating the severity of an allergic reaction
Basophil Histamine Release AssayAt baselineThe histamine release when in contact with the fish oil is compared with the histamine release when in contact with the positive control: Phorbol 12-myristate 13-acetate (PMA) + ionomycin. A histamine release of \>10% compared to the positive control is considered a positive result.
Subjective allergic symptoms during oral provocationsAt 2 hours after each provocation or at the end of the provocation if terminated early (in case of allergic reaction).Subjective allergic symptoms (e.g. itchiness, throat irritation) are noted

Countries

Denmark

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026