Impact of Vitamin C on Pain Detection and Tolerance Threshold

NCT06971315 | Completed

• 1 other identifier: 2025-2991
• Study Type: interventional
• Target: 38
• Locations: 1 country
• Sites: 1

Brief Summary

Non-opioid treatments are increasingly sought after for managing acute pain. Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) (e.g., Advil, Motrin, Naproxen) combined with acetaminophen (e.g., Tylenol) have become an alternative for relieving acute pain. However, many patients cannot tolerate or have contraindications to NSAIDs and acetaminophen. There is therefore an urgent need for studies evaluating the analgesic effects of vitamin C in the context of acute pain. Our study is conducted with healthy volunteer participants receiving either vitamin C or a placebo to assess the analgesic effect of vitamin C by comparing pain detection and tolerance thresholds.

Conditions

Pain, Acute

Keywords

Vitamin C; Algometer; Pain detection; Pain threshold

Outcome Measures

Primary Outcomes (1)

• Pressure pain detection threshold (PPDT)

  Pressure pain detection threshold (PPDT) measured with an algometer one to three hours after the last dose of the study drug (24 hours after the first dose of vitamin C or placebo).

  24 hours

Secondary Outcomes (3)

• Pressure pain detection threshold one to three hours after the first study drug dose

  1 hours

• Pressure pain tolerance threshold (PPTT) one to three hours after the last dose of the study drug

  24 hours

• Pressure pain tolerance threshold (PPTT) one to three hours after the first dose of the study drug

  1 hour

Study Arms (2)

Vitamin C

EXPERIMENTAL

Three doses of 900 mg of vitamin C taken orally every 12 hours for 24 hours (baseline, 12 hours and 24 hours)

Dietary Supplement: Vitamin C

Placebo

PLACEBO COMPARATOR

Three doses of 900 mg of placebo taken orally every 12 hours for 24 hours (baseline, 12 hours and 24 hours)

Other: Placebo

Interventions

Placebo OTHER

Three doses of 900 mg placebo taken orally (baseline, 12 hours and 24 hours)

Placebo

Vitamin C DIETARY_SUPPLEMENT

Three doses of 900 mg vitamin C taken orally (baseline, 12 hours and 24 hours)

Vitamin C

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age ≥ 18 to 65 years old;
• No acute or chronic pain;
• No pain medication;
• French or English-speaking

You may not qualify if:

• Currently using vitamin C supplements;
• Pain in the last week or active cancer;
• Unavailable for follow-up;
• Allergy to milk (lactose in the placebo), or vitamin C,
• Treated with cyclosporine or warfarin (interaction with vitamin C);
• Pre-existing oxalate nephropathy, liver cirrhosis or hemochromatosis;
• Evidence of joint or overlying skin infection in the areas of testing.

Sponsors & Collaborators

• Centre Integre Universitaire de Sante et Services Sociaux du Nord de l'ile de Montreal: lead

Study Sites (1)

Hopital du Sacre-Coeur de Montreal

Montreal, Quebec, H4J 1C5, Canada

Location

MeSH Terms

Conditions

Acute Pain

Interventions

Ascorbic Acid

Condition Hierarchy (Ancestors)

Pain; Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Sugar Acids; Acids, Acyclic; Carboxylic Acids; Organic Chemicals; Hydroxy Acids; Carbohydrates

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Dr Emergency Medicine, Professor, Clinician Researcher

Model Details: Double-blind randomized placebo-controlled trial

Study Record Dates

• First Submitted: May 6, 2025
• First Posted: May 14, 2025
• Study Start: July 18, 2025
• Primary Completion: August 6, 2025
• Study Completion: December 19, 2025
• Last Updated: March 31, 2026

Record last verified: 2026-03

Locations

CA (1)