Ascaridole, a sensitizing component of tea tree oil, patch tested at 1%, 2% and 5%.

Ascaridole, a sensitizing component of tea tree oil, patch tested at 1%, 2% and 5%. - Ascaridole: 1%, 2% or 5%?

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

NL-OMON

Registry ID

NL-OMON37207

Enrollment

Registered

2012-10-23

Start date

2012-10-26

Completion date

Unknown

Last updated

2024-04-29

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

Conditions

contact allergy sensitization

Interventions

None listed

Eligibility

Age

18 Years to 99 Years

Inclusion criteria

Inclusion criteria: - Adulthood - Legal competence - Epicutanous allergy test in the UMCG between 01-05-2011 and 30-09-2012 - Positive reaction (at least +) for ascaridole or doubtfull reaction for 1% or irritant reaction for 5%

Exclusion criteria

Exclusion criteria: - Angry back in the past (fals positive reaction to some patch test substances, be accompanied by heavy itch) - Active skin disease on the back - Use of immunosuppressive drugs up to six weeks before inclusion - Pregnancy(wish)

Design outcomes

Primary

Measure	Time frame
We will perform an epicutanous allergy test with ascaridole on the back of the participants. The test results will be graded according to the guidelines of the International Contact Dermatitis Research Group (ICDRG). This will result in a -, +? , +, ++, +++ or IR (irritated) response. The back of the participant will be photgraphed.	—

Secondary

Measure	Time frame
The questionnaire will be used to possibly clarify the relevance of a contact allergy, thereupon the history of exposure will be labeled: certain, probable, possible, unlikely/not. When a patient had reacted with an itching dermatitis to at least one product containing tea tree oil and had reacted to other alternatives, this was labeled certain. The category Probable existed of patients, who had reacted to one or more products probably containing tea tree oil, but a specific product had not been identified as the cause of a clinical reaction. The third category was Possible; the patient had reacted to various products with or without tea tree oil. Substances other than tea tree oil could have been the cause of a reaction in this category of patients. If a patient had never come in contact with products containing tea tree oil, the relevance was labeled Unlikely/ not	—

Measure

Time frame

The questionnaire will be used to possibly clarify the relevance of a contact allergy, thereupon the history of exposure will be labeled: certain, probable, possible, unlikely/not. When a patient had reacted with an itching dermatitis to at least one product containing tea tree oil and had reacted to other alternatives, this was labeled *certain*. The category *Probable* existed of patients, who had reacted to one or more products probably containing tea tree oil, but a specific product had not been identified as the cause of a clinical reaction. The third category was *Possible*; the patient had reacted to various products with or without tea tree oil. Substances other than tea tree oil could have been the cause of a reaction in this category of patients. If a patient had never come in contact with products containing tea tree oil, the relevance was labeled *Unlikely/ not*

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Countries

Netherlands

Outcome results