A Phase 1 interventional study of Oral capsaicin and Topical capsaicin in Migraine, Cluster Headache and Trigeminal Autonomic Cephalgia, sponsored by The University of Texas Health Science Center, Houston. Enrolling by invitation at 1 site in United States. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-02-18.
Sponsored by The University of Texas Health Science Center, Houston · Phase 1, Interventional, and Basic science
This study investigates molecular and physical biomarkers of headaches in order to better understand mechanisms of these diseases.
There are 3 main parts:
1,657 studies on the registry are indexed under Migraine Disorders; 339 are open to participants now.
This study's planned enrollment of 371 is above the median of 80 across 1,269 interventional studies indexed under Migraine Disorders.
Browse Migraine Disorders studies →The University of Texas Health Science Center, Houston is the lead sponsor of 897 studies on the registry; 214 are open to participants now.
Of its 173 completed or terminated interventional studies of FDA-regulated products, 142 (82%) have results posted.
Counted across the registry records on this site, refreshed daily.
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:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Drug: Oral capsaicin
Drug: Oral capsaicin · Other: Medical Air
Drug: Oral capsaicin · Drug: Low Flow Oxygen
Drug: Oral capsaicin · Drug: High Flow Oxygen
Drug: Topical capsaicin
Drug: Topical capsaicin · Other: Medical Air
Drug: Topical capsaicin · Drug: Low Flow Oxygen
Drug: Topical capsaicin · Drug: High Flow Oxygen
Drug: Intranasal capsaicin
Drug: Intranasal capsaicin · Other: Medical Air
Drug: Intranasal capsaicin · Drug: Low Flow Oxygen
Drug: Intranasal capsaicin · Drug: High Flow Oxygen
Other: Cold Water Irrigation
Other: Cold Water Irrigation · Other: Medical Air
Other: Cold Water Irrigation · Drug: Low Flow Oxygen
Other: Cold Water Irrigation · Drug: High Flow Oxygen
Subjects will drink a solution with capsaicin
Capsaicin cream will be applied to the skin of the forehead, cheek, or leg
Capsaicin cream will be applied to the nostril
Subjects will be asked to drink up to 2000 ml of cold water or ice water (temperature 0-10 degrees Celsius) as fast as possible, either continuously or intermittently (i.e. 200-800 ml at a time)
Subjects will be exposed to medical air
Subjects will be exposed to oxygen gas between 1-9 L/min
Subjects will be exposed to oxygen gas between 10-25 L/min
Activation of trigeminoautonomic reflex as assessed by change in Calcitonin gene-related peptide (CGRP) levels from before stimulation to after stimulation.
Time frame: 10 minutes before pain stimulation and 10 minutes, 20 minutes, 30 minutes, 60 minutes, and 90 minutes after pain stimulation
Activation of trigeminoautonomic reflex as assessed by tear fluid production
The amount of tear fluid after each intervention will be measured via Schirmer strips
Time frame: 90 minutes after pain stimulation
Activation of trigeminoautonomic reflex as assessed by change in pituitary adenylate cyclase activating polypeptide-38 (PACAP-38) levels levels from before stimulation to after stimulation.
Time frame: 10 minutes before pain stimulation and 10 minutes, 20 minutes, 30 minutes, 60 minutes, and 90 minutes after pain stimulation
Activation of trigeminoautonomic reflex as assessed by saliva production
Time frame: 90 minutes after pain stimulation
Activation of trigeminoautonomic reflex as assessed by nasal fluid production
Time frame: 90 minutes after pain stimulation
Activation of trigeminoautonomic reflex as assessed by tactile threshold measurement with von Frey Filaments
Time frame: 90 minutes after pain stimulation
Activation of trigeminoautonomic reflex as assessed by dermal blood flow
Time frame: 90 minutes after pain stimulation
Plan to share: Undecided
No publications or documents are linked to this record.
Started Mar 2018 (actual). Primary completion is estimated for May 2028, 122 months after the start.
Of 53 phase 1 interventional studies under Migraine Disorders, half reached primary completion within 6 months of starting (the median), counting those still running; a quarter within 2 and three quarters within 19. This study's planned 122 months is above that.
How these figures are worked out, and which studies are left out of them.
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Studies of the drug tested here: Capsaicin
The University of Texas Health Science Center, Houston →