Diphenhydramine Causing Adverse Effects in Therapeutic UsePhase 4BENEXE2022NCT05586477
Diphenhydramine and Sweating
A Phase 4 study testing Diphenhydramine in people with Diphenhydramine Causing Adverse Effects in Therapeutic Use and Hyperthermia, run by Lakehead University at 1 site in Canada.
Trial summary
In 2012, it was estimated that nearly 1 in 4 Canadians suffer from allergic rhinitis. To add, 78% of individuals working in predisposing environments are predicted to develop occupational rhinitis. Read more about this study
- Who is it for?
- Ages 18 to 49 yearsHealthy volunteers can take part
- Conditions the study is for
- Diphenhydramine Causing Adverse Effects in Therapeutic Use, Hyperthermia, Allergic Rhinitis
- What is being tested?
- Diphenhydramine
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 20 participants
- Where
- 1 siteCanada
- Study dates
- 21 Nov 2022to 23 Jun 2023
- Phase
- Phase 4
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 49 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Able to safely perform ~60 minutes of moderate intensity exercise
- No known hypersensitivity to diphenhydramine
- Not on any prescribed medication
- Body-mass index (BMI) less than 30
Who cannot join
- Outside 18 - 49 years of age
- Diagnosed with any cardiovascular, respiratory, neurological or metabolic disease
- History of any cardiovascular, respiratory, neurological or metabolic disease
- Unable to exercise for 60 minutes at moderate intensity, or have a musculoskeletal injury
- BMI > or = 30
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Does Diphenhydramine Alter Thermoregulatory Responses During Exercise?
In 2012, it was estimated that nearly 1 in 4 Canadians suffer from allergic rhinitis. To add, 78% of individuals working in predisposing environments are predicted to develop occupational rhinitis. Currently, the most popular treatment for rhinitis is antihistamine medication such as diphenhydramine, a first-generation antihistamine sold commercially as Benadryl®. Due it its anticholinergic effects, diphenhydramine has been suggested to impair the whole body sweating response during heat stress, potentially leaving consumers at an increased risk of heat-related illness. This randomized control trial approved by Health Canada will investigate whether ingesting extra strength diphenhydramine (50mg) will alter whole-body sweat losses during 60 minutes of exercise.
- Conditions
- Diphenhydramine Causing Adverse Effects in Therapeutic Use, Hyperthermia, Allergic Rhinitis, Sweating
- Being tested
- Placebo, Diphenhydramine
- Keywords
- thermoregulation, diphenhydramine, anticholinergic, sweating
- Medical subject headings
- Hyperthermia, Rhinitis, Allergic
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PlaceboDrug
A placebo pill (i.e., sugar) will be consumed 2 h before intervention.
DiphenhydramineDrug
Extra strength Benadryl (DIN 02470144) will be consumed 2 h before intervention
| Study group | Role | What they receive |
|---|---|---|
| Intervention Order (Placebo - Diphenhydramine) | Other | On separate days, participants will march on a treadmill for 60 minutes at a fixed rate of oxygen consumption (~1.75 liters of oxygen consumption per minute) in ~28°C and 30% relative humidity Receives: Drug: Placebo; Drug: Diphenhydramine |
| Intervention Order (Diphenhydramine -Placebo) | Other | On separate days, participants will march on a treadmill for 60 minutes at a fixed rate of oxygen consumption (~1.75 liters of oxygen consumption per minute) in ~28°C and 30% relative humidity Receives: Drug: Placebo; Drug: Diphenhydramine |
What is being measured
The primary outcome is the main question the study is designed to answer.
Whole body sweat loss
Change in body mass from pre- to post-exercise corrected for respiratory and metabolic water losses using a digital platform scale accurate to +/- 2 grams.
Measured: Measured during both placebo and diphenhydramine intervention trials trials, separated by no more than 28 days
Secondary outcomes (1)
Change in rectal temperature
Change in rectal temperature from pre- to post- exercise using a pediatric grade thermistor
Measured: Measured during both placebo and diphenhydramine intervention trials trials, separated by no more than 28 days
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted19 Oct 2022
- Study start21 Nov 2022
- Primary completion23 Jun 2023
- Study completion23 Jun 2023
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Diphenhydramine Causing Adverse Effects in Therapeutic UseStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 4
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 20 participants (actual)
Sponsor and investigators
- Lead sponsor
- Lakehead University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Nicholas Ravanelli, PhD, Principal investigator, Lakehead University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05586477
- Sponsor's protocol ID
- 2022509
- Other IDs
- 265937
- Acronym
- BENEXE2022
- Status last verified
- Sep 2023
- First submitted
- 14 Oct 2022
- Last updated
- 13 Sep 2023
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Publications
Newhouse D, Mihalcin E, Lefebvre K, Nucci M, Ravanelli N. Thermal and Cardiovascular Responses during Exertional Heat Stress after Diphenhydramine Use: A Randomized Crossover Trial. Med Sci Sports Exerc. 2024 Dec 1;56(12):2328-2337. doi: 10.1249/MSS.0000000000003527. Epub 2024 Jul 31.
PubMed 39140777
Study at a glance
From the registry record, last updated by the sponsor on 13 Sep 2023. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Does Diphenhydramine Alter Thermoregulatory Responses During Exercise?
- ClinicalTrials.gov ID
- NCT05586477
- Acronym / sponsor ID
- BENEXE2022 / 2022509
- Conditions
- Diphenhydramine Causing Adverse Effects in Therapeutic Use, Hyperthermia, Allergic Rhinitis, Sweating
- Keywords
- thermoregulation, diphenhydramine, anticholinergic, sweating
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 20 participants (actual)
- Lead sponsor
- Lakehead UniversityUniversity, hospital or other
- Study start
- 21 Nov 2022 (actual)
- Primary completion
- 23 Jun 2023 (actual)
- Study completion
- 23 Jun 2023 (actual)
- First posted
- 19 Oct 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
In 2012, it was estimated that nearly 1 in 4 Canadians suffer from allergic rhinitis. To add, 78% of individuals working in predisposing environments are predicted to develop occupational rhinitis. Currently, the most popular treatment for rhinitis is antihistamine medication such as diphenhydramine, a first-generation antihistamine sold commercially as Benadryl®. Due it its anticholinergic effects, diphenhydramine has been suggested to impair the whole body sweating response during heat stress, potentially leaving consumers at an increased risk of heat-related illness. This randomized control trial approved by Health Canada will investigate whether ingesting extra strength diphenhydramine (50mg) will alter whole-body sweat losses during 60 minutes of exercise.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Intervention Order (Placebo - Diphenhydramine) | Other | Drug: Placebo, Drug: DiphenhydramineOn separate days, participants will march on a treadmill for 60 minutes at a fixed rate of oxygen consumption (~1.75 liters of oxygen consumption per minute) in ~28°C and 30% relative humidity |
| Intervention Order (Diphenhydramine -Placebo) | Other | Drug: Placebo, Drug: DiphenhydramineOn separate days, participants will march on a treadmill for 60 minutes at a fixed rate of oxygen consumption (~1.75 liters of oxygen consumption per minute) in ~28°C and 30% relative humidity |
Who may qualify
- Ages
- 18 to 49 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (4 listed)
- Able to safely perform ~60 minutes of moderate intensity exercise
- No known hypersensitivity to diphenhydramine
- Not on any prescribed medication
- Body-mass index (BMI) less than 30
Key exclusion criteria (5 listed)
- Outside 18 - 49 years of age
- Diagnosed with any cardiovascular, respiratory, neurological or metabolic disease
- History of any cardiovascular, respiratory, neurological or metabolic disease
- Unable to exercise for 60 minutes at moderate intensity, or have a musculoskeletal injury
- BMI > or = 30
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| PlaceboA placebo pill (i.e., sugar) will be consumed 2 h before intervention. | Drug | Intervention Order (Diphenhydramine -Placebo), Intervention Order (Placebo - Diphenhydramine) |
| DiphenhydramineExtra strength Benadryl (DIN 02470144) will be consumed 2 h before intervention | Drug | Intervention Order (Diphenhydramine -Placebo), Intervention Order (Placebo - Diphenhydramine) |
Primary outcome
Whole body sweat loss
Time frame: Measured during both placebo and diphenhydramine intervention trials trials, separated by no more than 28 days
Change in body mass from pre- to post-exercise corrected for respiratory and metabolic water losses using a digital platform scale accurate to +/- 2 grams.
1 secondary outcome
Change in rectal temperature
Time frame: Measured during both placebo and diphenhydramine intervention trials trials, separated by no more than 28 days
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 13 Sep 2023.
- Derived from this study: PubMed 39140777Newhouse D, Mihalcin E, Lefebvre K, Nucci M, Ravanelli N. Thermal and Cardiovascular Responses during Exertional Heat Stress after Diphenhydramine Use: A Randomized Crossover Trial. Med Sci Sports Exerc. 2024 Dec 1;56(12):2328-2337. doi: 10.1249/MSS.0000000000003527. Epub 2024 Jul 31.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Nicholas Ravanelli, PhD principal investigator
Lakehead University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Diphenhydramine in people with Diphenhydramine Causing Adverse Effects in Therapeutic Use and Hyperthermia, run by Lakehead University at 1 site in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 13 Sep 2023. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Whole body sweat loss (time frame: Measured during both placebo and diphenhydramine intervention trials trials, separated by no more than 28 days). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05586477, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 13 Sep 2023; AzTrials last refreshed its copy on 27 Oct 2026.