Does Mouthwash Raise Your Blood Pressure? What the Human Trials Found — and Which Rinses Actually Matter
Last updated: 10 October 2026
Why a Mouthwash Could Touch Blood Pressure at All
The idea sounds odd until you follow the nitrate. Leafy greens and beetroot are rich in dietary nitrate. Your body can't turn nitrate into the useful molecule directly; it relies on bacteria living on the back of the tongue to do the first step. A 2021 review in Nutrition Research Reviews by Alzahrani and colleagues sets out the chain: oral bacteria reduce nitrate to nitrite, nitrite is carried into the bloodstream, and from there it supports nitric oxide signalling that helps vessels relax. The authors of a 2019 study in Frontiers in Cellular and Infection Microbiology (Tribble and colleagues) put it in similar terms: the pathway "relies upon commensal oral bacteria located on the tongue dorsum."
So the hypothesis is simple. If a rinse sharply reduces those bacteria, less nitrite is made, and blood pressure may drift up slightly. The question is whether that actually shows up in people — and how big it is.
What the Human Trials Actually Measured
Most "mouthwash and blood pressure" articles quote one study and a scary headline. Here is what the trials report side by side, using the figures set out in the Alzahrani review and, for Bondonno and Tribble, their own abstracts. Treat the sample sizes as the headline: every one of these studies is small.
| Study | Who / how long | Rinse tested | What was found |
|---|---|---|---|
| Kapil et al., 2013 (as reported in the Alzahrani review) | 19 normotensive adults, 7 days | Chlorhexidine 0.2% | Clinic systolic +3.5 mmHg (P=0.003), diastolic +2.2 (P=0.038); home readings +2.9 / +2.0; the rise tracked with lower plasma nitrite |
| Bondonno et al., 2015, American Journal of Hypertension | 15 treated hypertensive adults (mean age 65), randomised crossover, 3 days | Antibacterial mouthwash vs water | Systolic +2.3 mmHg (95% CI 0.5–4.0; P=0.01); diastolic and cGMP no significant change; plasma nitrite only a trend (P=0.09) |
| Woessner et al., 2016, Nitric Oxide (figures via the Alzahrani review) | 12 men, after a nitrate load | Three strengths: chlorhexidine, a cetylpyridinium (Cepacol) rinse, an essential-oil (Listerine) rinse | Plasma nitrite fell in a stepwise way with rinse strength; systolic at 4 h was 2–5 mmHg higher after chlorhexidine and Cepacol than after control or Listerine; diastolic no significant change |
| Tribble et al., 2019 | 27 enrolled healthy adults, 0.12% twice daily for 1 week | Chlorhexidine 0.12% | Significant average systolic rise, but individuals diverged: 13 changed by more than 5 mmHg — 9 up, 4 down |
| Sundqvist et al., 2016 (via the review) | 17 women | Chlorhexidine vs placebo | No effect on clinic or 24-hour blood pressure, or on plasma nitrate/nitrite |
| McDonagh et al., 2015 (via the review) | 12 adults, beetroot juice plus rinse | Strong antibacterial rinse | Resting blood pressure not significantly changed; nitrite rise after beetroot juice was blunted |
| Bondonno et al., 2012 (via the review) | 16 women | Antibacterial toothpaste | No effect on nitrate levels — the review suggests teeth harbour fewer nitrate-reducing bacteria than the tongue |
Two things stand out. First, the rises are small: 2 to 3.5 mmHg is within the range that ordinary day-to-day variation can produce, which is why the Alzahrani review warns that "these findings may have been influenced by the large inter-individual variability" in blood pressure. Second, the pattern follows strength. Chlorhexidine shows the clearest effect; a milder essential-oil rinse looked like the control group in Woessner's data; and the antibacterial toothpaste study found nothing. Per the review's own tally, its evidence base was 12 studies (nine human, three animal), and its conclusion was that "the limited number of studies performed make it difficult to draw any firm conclusions."
Where the Evidence Pushes Back
A fair reading has to include the cautions, and the sources supply them.
Chlorhexidine doesn't wipe the tongue clean. In Tribble's own data the rinse "caused a significant reduction in bacterial viability, but this effect was only a 10-fold reduction," and the authors report that it does not eradicate viable tongue bacteria. They also found that how often people cleaned their tongue was associated with how their blood pressure responded — one reason individual results diverged.
The headline claim ran ahead of the science. When the 2013 chlorhexidine study hit the news as "Mouthwashes can raise risk of heart attack and strokes," Dr Chris Hope of the University of Liverpool's oral biology department wrote in 2014 that the core findings "appear credible" but that the claim that fewer oral bacteria directly raised blood pressure was "perhaps less clear" — and that the coverage ignored the well-established links between dental plaque and cardiovascular disease.
The long-term data show no clear harm or benefit. A 2023 cohort study in the British Dental Journal by Janket and colleagues followed people for 18.8 years. Better oral hygiene was associated with lower cardiovascular mortality (HR 0.49, 95% CI 0.27–0.87), and the authors report that "mouthwash usage did not change OHS effects" and that it "did not show any long-term harm or benefit on CVD mortality." That is an association from observational data, not proof either way — but it doesn't support alarm about ordinary rinsing.
Dentists' view: low risk for most people. Dr Hsun-Liang (Albert) Chan, chair of periodontology at Ohio State University's College of Dentistry, says mouthwash is unlikely to seriously disrupt oral bacteria, adding that "the chance is very low, especially if you use it on a temporary basis" (Ohio State Health & Discovery, March 2024).
Which Rinse Is Which? A Label Decoder
"Antiseptic" covers very different products. The American Dental Association's mouthrinse guidance splits rinses into cosmetic ones, which "may temporarily control bad breath and leave behind a pleasant taste," and therapeutic ones, whose actives include cetylpyridinium chloride, chlorhexidine, essential oils, fluoride and peroxide. In the US, the ADA notes chlorhexidine is prescription-only, while essential-oil rinses are over the counter.
| Active on the label | Typical use | What the nitrate/blood-pressure trials show | Other known trade-offs |
|---|---|---|---|
| Chlorhexidine (0.12%–0.2%) | Short courses, often prescribed or after dental procedures | Strongest effect on nitrite and systolic pressure; mixed individual responses; one null trial | Staining, taste change; the FDA label for Peridex reports measurable extra stain in 56% of users vs 35% of controls at six months |
| Cetylpyridinium chloride (CPC) | Everyday "antibacterial" and breath rinses | Partly blunted nitrite in the one trial that tested it (Cepacol); systolic 2–5 mmHg higher at 4 h in that small study | ADA: CPC and chlorhexidine "may cause brown staining of teeth, tongue, and/or restorations" |
| Essential oils (eucalyptol, menthol, thymol, methyl salicylate) | OTC antiplaque rinses | Looked like control on systolic pressure in the one trial that included one | Often contain alcohol, which the ADA notes can be drying |
| Fluoride-only or cosmetic rinses | Cavity protection, fresh taste | Not tested in these nitrate trials — no data either way | Fluoride rinses are not substitutes for mechanical cleaning |
One honest limitation: this table reflects what was actually studied. "No data" does not mean "safe" or "unsafe" — it means nobody has measured it. And the ADA is clear on the bigger picture: "use of a mouthrinse is not a substitute for mechanical oral hygiene."
The 5-Step Check Before You Worry
- Find the active ingredient. Look for "chlorhexidine gluconate" or "cetylpyridinium chloride" in the Drug Facts or ingredient panel. If neither is there, the trial evidence above doesn't directly apply to your rinse.
- Ask why you're using it. A short chlorhexidine course after dental work or for a specific problem is a clinical decision. The Cochrane review by James and colleagues (2017) found 4 weeks or more of chlorhexidine causes extrinsic tooth staining — one reason it's typically a time-limited tool, not a daily habit.
- If you take blood pressure medication or have hypertension, mention your rinse at your next appointment. Bondonno's participants were treated hypertensives, so the effect was seen in people who were already on treatment. Do not stop either on your own.
- Run a simple home log if you're curious. Take two readings at the same time each morning for a week on your usual rinse, then a week without it (if your dentist agrees it's not needed). With effects this small and variation this large, only a consistent pattern means anything — and bring it to your clinician rather than interpreting it alone.
- Keep the basics. Brushing, interdental cleaning and gentle tongue care remain the foundation. Our guide to building a natural gum-health routine covers what to keep and what to skip.
If You'd Rather Not Rely on an Antiseptic Rinse: Dental Pro 7
Nothing in this evidence says everyone should abandon mouthwash. But if you want a gum-care routine that doesn't hinge on chlorhexidine or CPC, Dental Pro 7 is built differently. It's a 100% water-free botanical lipid concentrate, formulated by S. C. Aris, made from eleven named botanicals — including immortelle helichrysum, pomegranate seed, black cumin seed, wild clove, white thyme and a peppermint–spearmint–wild mint freshness blend. There is no chlorhexidine or cetylpyridinium chloride in it, no SLS or foaming agents, no fluoride, no preservatives or parabens, and no water at all.
The idea is Lipid-Lock: because the formula is water-free, it stays on the gum line for hours rather than rinsing away in seconds, which is how it supports the appearance of firmer, pinker, healthier-looking gums and fresher breath. Use it in place of toothpaste: four drops on a dry toothbrush, brush gently for about two minutes, then spit — do not rinse with water. (DP7 Pro Rinse is a separate product, diluted in water, for people who like to rinse.)
To be clear about what we are and aren't claiming: Dental Pro 7 is not an antiseptic, makes no antibacterial claim, and has not been studied in nitrate or blood-pressure trials. It is a cosmetic product that supports how your gum line looks and feels, not a treatment for gingivitis, gum disease or any condition, and not a replacement for the cavity protection fluoride provides. Dental Pro 7 is rated 4.9 out of 5 from 293 reviews, has sold more than 500,000 bottles, and carries a 90-day money-back guarantee. It's vegan and non-GMO, and contains naturally occurring eugenol, limonene and linalool — so it is not an "allergen-free" product.
Frequently Asked Questions
Does mouthwash raise blood pressure?
In small, short trials, strongly antibacterial rinses — chlorhexidine above all — were followed by systolic increases of about 2 to 3.5 mmHg on average. Other trials found no effect, individual responses varied, and an 18.8-year cohort study found no long-term harm or benefit for cardiovascular mortality. The evidence is suggestive, not conclusive.
Which mouthwash is linked to higher blood pressure?
The clearest signal is chlorhexidine (0.12%–0.2%). A cetylpyridinium-chloride rinse partly blunted nitrite in one small trial, and an essential-oil rinse looked like the control group. Fluoride-only and cosmetic rinses haven't been tested in these studies.
Why would killing mouth bacteria affect blood pressure?
Bacteria on the tongue convert dietary nitrate into nitrite, which supports nitric oxide signalling and vessel relaxation. Reduce those bacteria and less nitrite is made. Chlorhexidine, though, only reduced viable tongue bacteria about 10-fold in one study rather than eliminating them.
Should I stop using mouthwash if I have high blood pressure?
Don't stop anything on your own. Tell your doctor or dentist which rinse you use, check whether it contains chlorhexidine or CPC, and ask whether you need it. The people in the Bondonno trial were already on treatment for hypertension.
Does mouthwash kill the good bacteria in your mouth?
Short-term use is unlikely to seriously disrupt your oral bacteria, according to periodontologist Dr Hsun-Liang Chan of Ohio State University. Antiseptic rinses do reduce bacterial counts temporarily; the open question is whether that matters for blood pressure, which the trials suggest it may, slightly, for some people.
Does Dental Pro 7 contain chlorhexidine?
No. Dental Pro 7 is a water-free botanical lipid concentrate with no chlorhexidine, cetylpyridinium chloride, SLS, fluoride, preservatives or parabens. It is a cosmetic product, makes no antibacterial claim, and has not been tested in blood-pressure studies.
Sources
- Alzahrani HS, Jackson KG, Hobbs DA, Lovegrove JA. "The role of dietary nitrate and the oral microbiome on blood pressure and vascular tone." Nutrition Research Reviews 2021;34:222–239. (Source for the Kapil 2013, Woessner 2016, Sundqvist 2016, McDonagh 2015 and Bondonno 2012 figures.)
- Bondonno CP et al. "Antibacterial mouthwash blunts oral nitrate reduction and increases blood pressure in treated hypertensive men and women." American Journal of Hypertension 2015;28(5):572–575 (abstract).
- Tribble GD et al. "Frequency of Tongue Cleaning Impacts the Human Tongue Microbiome Composition and Enterosalivary Circulation of Nitrate." Frontiers in Cellular and Infection Microbiology 2019;9:39.
- Hope C. "Viewpoint: Will your mouthwash kill you?" University of Liverpool, 27 January 2014 (opinion piece).
- Janket S-J et al. "Oral hygiene, mouthwash usage and cardiovascular mortality during 18.8 years of follow-up." British Dental Journal 2023 (abstract).
- Chan H-L. "Does mouthwash kill the mouth's healthy bacteria?" Ohio State Health & Discovery, 21 March 2024.
- American Dental Association, "Mouthrinse (Mouthwash)" (Oral Health Topics).
- James P et al. "Chlorhexidine mouthrinse as an adjunctive treatment for gingival health." Cochrane Database of Systematic Reviews 2017, CD008676.
- U.S. FDA-approved label, PERIDEX (chlorhexidine gluconate 0.12%) oral rinse, NDA019028 (DailyMed).
This article is for general information and is not a substitute for professional dental or medical advice, diagnosis, or treatment. Do not stop or change any prescribed mouthrinse or blood pressure medication without speaking to your doctor or dentist. CallNature products are cosmetics and are not intended to diagnose, treat, cure, or prevent any disease. If you have signs of gum disease or a dental concern, please see a dentist.