Recruiting

CAlgary SAlt

Sponsor:

University of Calgary

Code:

NCT05924646

Conditions

Postural Orthostatic Tachycardia Syndrome

Eligibility Criteria

Sex: All

Age: 18 - 60

Healthy Volunteers: Not accepted

Interventions

Sodium Chloride Capsules

Microcystalline Cellulose Capsules

Study Details

Brief summary:

Many patients with postural orthostatic tachycardia syndrome (POTS) have decreased plasma volume. Current POTS guidelines recommend \~10 g of salt and 2-3 L of fluid per day. Despite this recommendation, there is no long term data evaluating the use of salt in POTS. This randomized, placebo-controlled cross-over trial will evaluate a high salt diet, compared to a normal salt diet over a period of 3 months. Participants will complete 3 in lab evaluations including autonomic function testing, tilt table testing, blood volume and urine sodium evaluation, plasma catecholamine measurements and and cytokine measurements.

Conditions

Postural Orthostatic Tachycardia Syndrome

Study ID

NCT05924646

Start date

May 7, 2024

Status verified date

Apr, 2026

Completion date

Dec 31, 2028

Anticipated

Primary completion date

Jun 30, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 60

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Physician Diagnosis of POTS as defined by the CCS Consensus Statement and as follows:
  • Sustained, excessive orthostatic tachycardia ≥ 30 bpm within 10 minutes standing.
  • Absence of orthostatic hypotension (>20/10 mmHg decrease) within 3 minutes standing.
  • Chronic orthostatic symptoms that improve with recumbence.
  • Age 18-60 years old.
  • Ability to attend the Calgary Autonomic Research Clinic in Calgary.
  • Resident of Canada

Exclusion Criteria:

  • Overt cause for postural tachycardia (i.e., acute dehydration, thyroid disease)
  • Participants with somatization or severe anxiety symptoms will be excluded
  • Pregnant (self-reported)
  • Underlying causes of tachycardia including acute hypovolemia, endocrinopathy, anemia, anxiety, medication effects, recreational drug effects, and prolonged bedrest.
  • Other factors which in the investigator's opinion would prevent the participant from completing the protocol, including poor compliance during previous studies
  • Fludrocortisone use (due to effects on renal Na+ handling)
  • Patients who have received IV saline in the 2 months preceding the study or who plan to receive it during the course of the study

Study Design

Enrollment

50 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Moderate Dietary Salt Plus Additional Salt

6 grams of salt in slow release capsules combined with 6 grams of salt in the diet.

placebo comparator: Moderate Dietary Salt Alone

6 grams of microcrystalline cellulose in slow release capsules combined with 6 grams of salt in the diet.

Interventions

Sodium Chloride Capsules

Table salt in slow release capsules.

Microcystalline Cellulose Capsules

Microcrystalline Cellulose Capsules (Placebo)

Primary outcome measure

  • Upright Heart Rate [ Time Frame: 10 Minutes ]

Central Contacts and Locations

Central contacts

Satish R Raj, MD MSCI

4032106152autonomic.research@ucalgary.ca

Tanya Siddiqui, MBBS

autonomic.research@ucalgary.ca

Locations

University of Calgary

Recruiting

Calgary, Alberta, Canada, T2N 4Z6

Contacts

Satish R Raj, MD, MSCI

403-210-6152autonomic.research@ucalgary.ca

More Information

Sponsor

University of Calgary

Last update posted

May 7, 2026

Last verified

Apr, 2026

Keywords

  • Sodium
  • Salt
  • Treatment

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of Calgary on 2026-05-07.