An observational study in Urticaria Acute, sponsored by Ankara Etlik City Hospital. Completed at 1 site in Turkey (Türkiye). Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-10-08.
Sponsored by Ankara Etlik City Hospital · Observational
The goal of this observational study is to learn whether adding a single oral dose of colloidal silicon dioxide, an enterosorbent, to routine emergency department treatment is associated with faster early improvement in adults with acute urticaria. The main question it aims to answer is: Is the change in urticaria activity over the first 2 hours different in patients who receive colloidal silicon dioxide in addition to intravenous pheniramine compared with patients who receive intravenous pheniramine alone? Treatment is chosen by the treating emergency physician as part of routine care, before patients are approached for the study. Participants are assessed before treatment and at 1 and 2 hours, and are contacted by telephone at 24 hours.
This prospective, single-centre observational pilot study was conducted in the adult emergency department of Ankara Etlik City Hospital. Adults aged 18 to 65 years presenting within 4 hours of the onset of acute urticaria without systemic involvement were screened. All patients received intravenous pheniramine maleate 45.5 mg as routine treatment. Treating physicians, who were not part of the study team, independently decided as part of routine practice whether to add a single 3 g oral dose of colloidal silicon dioxide (Polisorb MP, a CE-marked medical device) suspended in water. Study groups were defined by the treatment received; the investigators did not assign treatment. Enrolment was capped at 35 patients per group.
Urticaria activity was assessed with a point-in-time adaptation of the Urticaria Activity Score (UAS; wheal and pruritus components, total 0-6) before treatment (T0) and at 1 hour (T1) and 2 hours (T2). Itch intensity was also rated on a 0-10 visual analogue scale. Rescue medication during the first 2 hours, adverse events, and relapse, return visits and additional medication use at a 24-hour telephone follow-up were recorded. The primary outcome is the change in UAS from T0 to T2, compared between groups with baseline-adjusted linear regression (ANCOVA).
1,721 studies on the registry are indexed under Emergencies; 335 are open to participants now.
This study's enrollment of 70 is below the median of 351 across 726 observational studies indexed under Emergencies.
Browse Emergencies studies →Ankara Etlik City Hospital is the lead sponsor of 172 studies on the registry; 77 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Consecutive adults aged 18 to 65 years presenting to the adult emergency department of Ankara Etlik City Hospital with acute urticaria within 4 hours of symptom onset and without systemic involvement, treated with intravenous pheniramine with or without oral colloidal silicon dioxide as decided by the treating physician.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Adults with acute urticaria who received routine intravenous pheniramine maleate 45.5 mg plus a single 3 g oral dose of colloidal silicon dioxide, as decided by the treating emergency physician (n=35).
Device: Colloidal silicon dioxide
Adults with acute urticaria who received routine intravenous pheniramine maleate 45.5 mg without colloidal silicon dioxide, as decided by the treating emergency physician (n=35 enrolled; 2 withdrew consent).
Single oral dose of 3 g colloidal (highly dispersed) silicon dioxide, a CE-marked enterosorbent medical device, suspended in 100-150 mL of water and taken at presentation, in addition to routine intravenous pheniramine. Use was decided by the treating emergency physician as part of routine care, not assigned by the study.
Also known as: Polisorb MP
Change in Urticaria Activity Score (UAS) from baseline to 2 hours
Point-in-time adaptation of the Urticaria Activity Score: wheal number (0-3) and pruritus intensity (0-3), total 0-6, with higher scores indicating more severe urticaria activity. Wheals were assessed by the investigator and pruritus was reported by the patient. The change from before treatment (T0) to 2 hours after treatment (T2) is compared between groups with adjustment for baseline UAS.
Time frame: Before treatment (baseline) and 2 hours after treatment
Change in itch visual analogue scale (VAS) score from baseline to 2 hours
Itch intensity rated by the patient on a 0-10 visual analogue scale (0 = no itch, 10 = worst imaginable itch), assessed before treatment and at 1 and 2 hours.
Time frame: Before treatment (baseline), 1 hour and 2 hours after treatment
Change in Urticaria Activity Score (UAS) from baseline to 1 hour
Point-in-time adaptation of the UAS (0-6; higher scores indicate more severe activity), change from before treatment to 1 hour after treatment.
Time frame: Before treatment (baseline) and 1 hour after treatment
Proportion of patients with at least 50% reduction in UAS at 2 hours
Proportion of patients whose UAS decreased by at least 50% from baseline at 2 hours. Response defined as a reduction of at least 2 points or at least 50%, and early response as at least 50% reduction at 1 hour, are also reported.
Time frame: Baseline, 1 hour and 2 hours after treatment
Proportion of patients receiving rescue medication
Use of additional antihistamine or systemic corticosteroid given at the treating physician's discretion during the first 2 hours.
Time frame: From treatment to 2 hours
Proportion of patients with relapse at 24 hours
Recurrence or worsening of urticarial symptoms reported at a 24-hour telephone follow-up; return visits and additional medication use within 24 hours were also recorded.
Time frame: 24 hours after treatment
Number of patients with adverse events
Nausea, vomiting, constipation, abdominal discomfort, sedation or dizziness elicited with standard questions at 2 hours and at the 24-hour telephone follow-up.
Time frame: From treatment to 24 hours
Plan to share: No — De-identified individual participant data are not deposited in a public repository; the anonymised data set is available from the principal investigator on reasonable request.
No publications or documents are linked to this record.
Ran from Aug 2026 to primary completion in Sep 2026, 1 month.
Of 310 non-industry observational studies under Emergencies, half reached primary completion within 14 months of starting (the median), counting those still running; a quarter within 5 and three quarters within 30. This study's 1 month is below that.
Counting every sponsor, half of 321 studies reached it within 14 months; a quarter within 5 and three quarters within 30.
Emergencies covers many different conditions, not one, so the studies compared here vary widely. Read these figures as a rough guide.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is completed, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.