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Not yet taking people in United StatesEarly phase 1

Guanfacine and Cromolyn Sodium for POTS: The DBPOTS Trial

Key facts

Who runs it
Johns Hopkins University
Where
Baltimore, United StatesSee the site
Trial code
Status
Not yet recruiting
Phase
Early phase 1
People taking part
25 people, planned
Starts
20 Nov 2026
Expected to end
2 Feb 2028
Type of study
Interventional, 3 groupsOne group gets a placebo (a dummy treatment), for comparison.
Treatments tested
  • Guanfacine (GFC)
  • Cromolyn Sodium
  • Placebo
Record updated
12 November 2026

Who can take part

Age
18 years to 100 years
Sex
Women and men
Healthy volunteers
Cannot take part

The registry criteria, word for word

Show all 19 criteriaShow less

Who can take part

  • Documented diagnosis of POTS per current consensus guidelines:
  • a heart rate increase of ≥30 bpm within the first 10 minutes of standing or tilt-table testing, without orthostatic hypotension (systolic BP drop ≥20 mmHg)
  • Frequent symptoms of orthostatic intolerance (e.g., dizziness, palpitations, GI complaints) persisting ≥3 months
  • Symptom onset within 3 months of a recognized POTS trigger (e.g., infection, vaccination, injury, surgery, pregnancy, or puberty)
  • Symptomatic response to mediator-targeting medications (e.g., antihistamines, mast cell stabilizers) - also eligible
  • Presence of flushing, pruritis, urticaria, or angioedema - also eligible
  • Alternative diagnoses must be excluded via prior clinical workup and laboratory assessment

Who cannot take part

  • Current use of medications that cannot be safely discontinued during study enrollment (safety-based exclusion)
  • Active infection,
  • Adrenal insufficiency,
  • Paraneoplastic conditions
  • Active neurologic disease (including stroke and epilepsy)
  • Alternative medical causes for symptoms, including:
  • Anemia,
  • Dehydration,
  • Hyperthyroidism,
  • Pheochromocytoma,
  • Prolonged immobilization
  • Pregnancy or breastfeeding

Check if you might fit

Answer for yourself. This is not a decision: only the study team can say whether you can take part.

  • Are you between 18 and 100 years old?

Where in United States

  • Johns Hopkins HospitalBaltimore, United StatesContact: Malcolm Brock, MD (principal investigator)No longer taking part

About the trial

What the trial wants to find out

The goal of this clinical trial is to learn whether guanfacine or cromolyn sodium can improve symptoms and physical functioning in adults with Postural Orthostatic Tachycardia Syndrome (POTS). Both medications are FDA-approved for other conditions but are investigational for the treatment of POTS.

Read full original descriptionShow less

The main questions this study aims to answer are:

Does treatment with guanfacine or cromolyn sodium improve physical functioning in adults with POTS compared with placebo? Does treatment with guanfacine or cromolyn sodium improve fatigue, cognitive function ("brain fog"), gastrointestinal symptoms, and overall symptom burden in adults with POTS?

Researchers will compare guanfacine, cromolyn sodium, and placebo to determine whether either active treatment provides greater improvement in symptoms and physical functioning than placebo.

Participants will:

Be randomly assigned to receive guanfacine, cromolyn sodium, and placebo during separate 4-week treatment periods in a randomized, double-blind crossover study.

Continue standard non-drug POTS management, including recommendations for fluid and salt intake, exercise, compression garments, and other lifestyle measures.

Complete questionnaires that measure physical function, fatigue, cognitive symptoms, gastrointestinal symptoms, and overall health throughout the study.

Attend scheduled study visits for safety monitoring and assessment of study outcomes.

Provide blood, urine, and sputum samples so researchers can evaluate biomarkers related to POTS and better understand how these treatments may work.

The 3 groups in the trial

  • GuanfacineTreatment being tested

    Participants receive oral guanfacine during one 4-week treatment period, with dose escalation permitted according to protocol if clinically indicated.

    Treatment: Guanfacine (GFC), Cromolyn Sodium, and Placebo

  • Cromolyn SodiumTreatment being tested

    Participants receive oral cromolyn sodium during one 4-week treatment period, with protocol-defined dose escalation if needed.

    Treatment: Guanfacine (GFC), Cromolyn Sodium, and Placebo

  • PlaceboPlacebo, for comparison

    Participants receive matched placebo during one 4-week treatment period to maintain blinding.

    Treatment: Guanfacine (GFC), Cromolyn Sodium, and Placebo

Questions to ask the study team

  1. How often do I need to come in, and for how long each time?
  2. Are travel costs paid?
  3. Can I keep my own doctor?
  4. What happens if I want to stop?

Contact the study team: see the registry record → Contacts and Locations

Print a page for my doctor

Data and sources

Registry record
Listed on ClinicalTrials.gov.
Official title
Efficacy and Mechanisms of Guanfacine and Cromolyn Sodium in Adults With Postural Orthostatic Tachycardia Syndrome (POTS): A Randomized, Double-Blind, Placebo-Controlled Crossover Clinical Trial. Acronym is DBPOTS (Double Blind POTS)
Fit questions
Built from NCT07757555, who can take part
Record updated
12 November 2026