Mouthrinse (Mouthwash)

Key Points

  • There are two main types of mouthrinse: cosmetic and therapeutic.
  • Therapeutic mouthrinses are available both over-the-counter and by prescription, depending on the formulation.
  • There are therapeutic mouthrinses that help reduce or control plaque, gingivitis, bad breath, and tooth decay.
  • Children younger than the age of 6 should not use mouthrinse, unless directed by a dentist, because they may swallow large amounts of the liquid inadvertently.
  • A company earns the ADA Seal of Acceptance by providing scientific evidence that demonstrates the safety and efficacy of its product, which the ADA Council on Scientific Affairs carefully evaluates according to objective requirements.


While not a replacement for daily brushing and flossing, use of mouthrinse (also called mouthwash) may be a helpful addition to the daily oral hygiene routine for some people. Like interdental cleaners, mouthrinse offers the benefit of reaching areas not easily accessed by a toothbrush. The question of whether to rinse before or after brushing may depend on personal preference; however, to maximize benefit from the oral care products used, manufacturers may recommend a specific order for their use, depending on ingredients.  For example, some dentifrice ingredients (like calcium hydroxide or aluminum hydroxide) can form a complex with fluoride ions and reduce a mouthrinse’s effectiveness. Therefore, vigorous rinsing with water may be recommended after brushing and before rinsing if these ingredients are present.1

Mouthrinse is not recommended for children younger than 6 years of age unless directed by a dentist.  Swallowing reflexes may not be well developed in children this young, and they may swallow large amounts of the mouthrinse, which can trigger adverse events—like nausea, vomiting, and intoxication (due to the alcohol content in some rinses).1, 2 Check the product label for specific precautions and age recommendations.

Types of Mouthrinse

Broadly speaking, there are two types of mouthrinse: cosmetic and therapeutic.  Cosmetic mouthrinses may temporarily control bad breath and leave behind a pleasant taste, but have no chemical or biological application beyond their temporary benefit. For example, if a product doesn’t kill bacteria associated with bad breath, then its benefit is considered to be solely cosmetic. Therapeutic mouthrinses, by contrast, have active ingredients intended to help control or reduce conditions like bad breath, gingivitis, plaque, and tooth decay.

Active ingredients that may be used in therapeutic mouthrinse include:

  • cetylpyridinium chloride;
  • chlorhexidine;
  • essential oils;
  • fluoride;
  • peroxide.

Cetylpyridinium chloride may be added to reduce bad breath.3  Both chlorhexidine and essential oils can be used to help control plaque and gingivitis.4, 5 Fluoride is a proven agent in helping to prevent decay.6 Peroxide is present in several whitening mouthrinses.1 Therapeutic mouthrinse is available both over-the-counter and by prescription, depending on the formulation.  For example, mouthrinses containing essential oils are available in stores, while those containing chlorhexidine are available only by prescription.

Clinical Considerations

Some of the conditions mouthrinses are designed to address are discussed in the following sections.

Alveolar Osteitis (Dry Socket)

Alveolar osteitis (AO), also known as dry socket, is a common postoperative condition following dental extraction procedures, particularly those of the third molar.7AO occurs when the fibrin clot that forms following extraction is dislodged. AO usually results in intense pain in and around the extraction site 2 to 3 days after the procedure. A recent systematic review and meta-analysis of 18 trials7 has shown chlorhexidine, without the use of antibiotics, to be effective for lowering the risk of AO following third molar extractions.  A moderate, but statistically not significant, increase in efficacy was seen in the gel formulation compared with the rinse formulation; however, the review could not recommend a specific dosing regimen. Studies included in the review reported minor, nonclinical reactions to chlorhexidine, including staining of teeth, dentures, and tongue, and altered taste.

Oral Malodor (Bad Breath)

Volatile sulfur compounds (VSCs) are the major contributing factor to oral malodor or bad breath. They arise from a variety of sources (e.g., breakdown of food, dental plaque and bacteria associated with oral disease).3 Cosmetic mouthrinses can temporarily mask bad breath and provide a pleasing flavor, but do not have an effect on bacteria or VSCs. Mouthrinses with therapeutic agents like antimicrobials, however, may be effective for more long-term control of bad breath. Antimicrobials in mouthrinse formulations include chlorhexidine, chlorine dioxide, cetylpyridinium chloride, and essential oils (e.g., eucalyptol, menthol, thymol, and methyl salicylate). Other agents used in mouthrinses to inhibit odor-causing compounds include zinc salts, ketone, terpene, and ionone.1 Although the combination of chlorhexidine and cetylpyridinium chloride plus zinc lactate has been shown to significantly reduce bad breath, it also may significantly contribute to tooth staining.3, 8

Plaque and Gingivitis

When used in mouthrinses, antimicrobial ingredients like cetylpyridinium chloride, chlorhexidine, and essential oils have been shown to help reduce plaque and gingivitis when combined with daily brushing and flossing.5, 9 While some studies have found that chlorhexidine achieved better plaque control than essential oils, no difference was observed with respect to gingivitis control. Cetylpyridinium chloride and chlorhexidine may cause brown staining of teeth, tongue, and/or restorations.4

Preprocedural Mouthrinse

Some dental equipment and procedures, including ultrasonic scalers, air polishing, air-water syringe and tooth polishing with air turbine handpieces or air abrasion, generate aerosols, a mix of liquid and solid particles.10, 11Aerosols can remain airborne for up to four hours before settling on surrounding surfaces.12 In addition to settling on environmental surfaces, aerosols containing microorganisms can be inhaled by dental care providers, posing a risk for disease transmission.11Respiratory diseases associated with aerosols include influenza, and tuberculosis, as well as COVID-19 SARS-CoV-2.110, 11

Research suggests that having a patient use a mouthrinse prior to treatment may reduce the amount of aerosolized microorganisms. However, there is no evidence that preprocedural mouthrinse protects against clinical disease among dental staff.11

Bacteriocidal effect of preprocedural mouthrinses. The evidence suggests that preprocedural mouthrinse is effective at reducing bacterial contamination in dental aerosols.12Certain antimicrobial rinse solutions used from 30 seconds to 2 minutes versus water or no rinse effectively reduced aerosol contamination produced during periodontal prophylaxis.12 For example. chlorhexidine (either 0.12 or 0.2%) is an effective antimicrobial solution for this purpose.12 One drawback, however, is that chlorhexidine can cause tooth staining, supragingival calculus formation, and a change in taste sensation.13Researchers also, though, have found comparable performance between chlorhexidine and cetylpyridinium chloride as a preprocedural rinse in reducing bacterial load in aerosols. 11

Virucidal effect of preprocedural mouthrinses. Although little clinical data have been collected ,12one small study found that preprocedural rinses, including normal saline, reduced SARS-CoV-2 viral load in saliva. 14

One review of four in vitro studies, however, found that a preprocedural rinse with chlorhexidine was effective at reducing viral load. 13Essential oils also were shown to have antiviral properties against enveloped viruses.13

Overall, there is a need for additional research concerning the role of preprocedural mouthrinses in preventing viral infections.12

Tooth Decay

Fluoride ions, which promote remineralization, may be provided by certain mouthrinses. A Cochrane systematic review found that regular use of fluoride mouthrinse reduced tooth decay in children, regardless of exposure to other sources of fluoride (i.e., fluoridated water or toothpaste containing fluoride).15

Topical Pain Relief

Mouthrinses that offer pain relief most commonly contain topical local anesthetics such as lidocaine, benzocaine/butamin/tetracaine hydrochloride, dyclonine hydrochloride, or phenol.1 In addition, sodium hyaluronate, polyvinylpyrrolidine and glycyrrhetinic acid may act as a barrier to relieve pain secondary to oral lesions, like aphthous ulcers.1


Mouthrinse may contribute to extrinsic stain reduction when either carbamide peroxide or hydrogen peroxide are among the active ingredients. Products that rely on carbamide peroxide typically contain 10 percent carbamide peroxide and may be dispensed by dentists to their patients for use at home.16 Mouthrinses that claim to whiten teeth also may contain 1.5 to 2 percent hydrogen peroxide.One study found that 12 weeks' use of mouthrinse containing hydrogen peroxide in this concentration range achieved similar color alteration as that achieved by 2 weeks' use of 10 percent carbamide peroxide whitening gel.17


Xerostomiais a reduction in the amount of saliva bathing the oral mucous membranes. Since the lack of saliva increases the risk of caries, a fluoride-containing mouthrinse may be helpful to those managing this problem. However, since alcohol can be drying, it may be prudent to recommend an alcohol-free mouthrinse.18Mouthrinses containing enzymes, cellulose derivatives and/or animal mucins can mimic the composition and feel of saliva and may provide additional relief from symptoms associated with xerostomia.1

Oral Cancer Concern

Alcohol consumption as well as alcohol and tobacco use are known risk factors for head and neck cancers.19Resulting from this has been the question of whether use of alcohol-containing mouthrinse increases risk of these cancers.20A recent systematic review and meta-analysis failed to find an association between mouthrinse use and oral cancer, use of alcohol-containing mouthrinse and oral cancer, or mouthrinse dose response and oral cancer.21

Information for Patients
  • Use prescription mouthrinses as directed (i.e., dose, frequency, time in mouth). If a dose is missed, use the rinse as soon as possible; doubling the dose will have no therapeutic effect.1
  • With over-the-counter products, look for mouthrinses that have the ADA Seal of Acceptance. The Seal shows that a company has provided data demonstrating that a product is safe and effective for the purpose claimed.
  • Using a mouthrinse does not take the place of optimal brushing and flossing.  Mouthrinses may offer additional benefit in terms of reducing the risk of bad breath, cavities, or gum disease; or for relief of dry mouth or pain from oral sores.
ADA Seal of Acceptance

Look for the ADA Seal—your assurance that the product has been objectively evaluated for safety and efficacy by an independent body of scientific experts, the ADA Council on Scientific Affairs. A company earns the ADA Seal for mouthrinse by producing scientific evidence demonstrating the safety and efficacy of its product, which is evaluated according to the objective requirements related to their claims.

Manufacturers of all types of mouthrinse who apply for the Seal must demonstrate that their products adhere to FDA regulations and meet the ANSI/ADA or ISO Standards for Oral Care products (wherever applicable). To qualify for the Seal of Acceptance, the company must demonstrate that their product meets applicable ADA Seal requirements, and must provide safety and efficacy data, to support the claims associated with their product. For example:

  • Manufacturers of mouthrinses that contain fluoride for reducing decay must demonstrate the total concentration of fluoride, and other parameters as per the standards. For additional active agents, or inactive agents that might be expected to interfere with fluoride, clinical anticaries studies may be required.
  • Manufacturers that claim control of gingivitis must substantiate this assertion by demonstrating statistically significant reduction in gingival inflammation and plaque formation or pathogenicity.
  • Manufacturers that claim their mouthrinse controls bad breath must provide data demonstrating that it reduces oral malodor when compared to a control over a meaningful period of time.
  • Manufacturers of mouthrinses designed to alleviate dry mouth must provide data showing that the product is safe and effective in temporarily relieving dry mouth symptoms, when used as directed.
  1. Mariotti AJ, Burrell, K.H. Mouthrinses and dentifrices. 5th ed. Chicago: American Dental Association and Physician's Desk Reference, Inc.; 2009.
  2. Weyant RJ, Tracy SL, Anselmo TT, et al. Topical fluoride for caries prevention: executive summary of the updated clinical recommendations and supporting systematic review. J Am Dent Assoc 2013;144(11):1279-91.
  3. Blom T, Slot DE, Quirynen M, Van der Weijden GA. The effect of mouthrinses on oral malodor: a systematic review. Int J Dent Hyg 2012;10(3):209-22.
  4. Van der Weijden FA, Van der Sluijs E, Ciancio SG, Slot DE. Can chemical mouthwash agents achieve plaque/gingivitis control? Dent Clin North Am 2015;59(4):799-829.
  5. Araujo MW, Charles CA, Weinstein RB, et al. Meta-analysis of the effect of an essential oil-containing mouthrinse on gingivitis and plaque. J Am Dent Assoc 2015;146(8):610-22.
  6. Fejerskov O, Thylstrup A, Larsen MJ. Rational use of fluorides in caries prevention. A concept based on possible cariostatic mechanisms. Acta Odontol Scand 1981;39(4):241-9.
  7. Rodriguez Sanchez F, Rodriguez Andres C, Arteagoitia Calvo I. Does chlorhexidine prevent alveolar osteitis after third molar extractions? Systematic review and meta-analysis. J Oral Maxillofac Surg 2017.
  8. Fedorowicz Z, Aljufairi H, Nasser M, Outhouse TL, Pedrazzi V. Mouthrinses for the treatment of halitosis. Cochrane Database Syst Rev 2008(4):CD006701.
  9. Sharma N, Charles CH, Lynch MC, et al. Adjunctive benefit of an essential oil-containing mouthrinse in reducing plaque and gingivitis in patients who brush and floss regularly: a six-month study. J Am Dent Assoc 2004;135(4):496-504.
  10. Harrel SK, Molinari J. Aerosols and splatter in dentistry: a brief review of the literature and infection control implications. J Am Dent Assoc 2004;135(4):429-37.
  11. Marui VC, Souto MLS, Rovai ES, et al. Efficacy of preprocedural mouthrinses in the reduction of microorganisms in aerosol: A systematic review. J Am Dent Assoc 2019;150(12):1015-26.e1.
  12. Mohd-Said S, Mohd-Dom TN, Suhaimi N, Rani H, McGrath C. Effectiveness of Pre-procedural Mouth Rinses in Reducing Aerosol Contamination During Periodontal Prophylaxis: A Systematic Review. Front Med (Lausanne) 2021;8:600769.
  13. Moosavi MS, Aminishakib P, Ansari M. Antiviral mouthwashes: possible benefit for COVID-19 with evidence-based approach. J Oral Microbiol 2020;12(1):1794363.
  14. Chaudhary P, Melkonyan A, Meethil A, et al. Estimating salivary carriage of severe acute respiratory syndrome coronavirus 2 in nonsymptomatic people and efficacy of mouthrinse in reducing viral load: A randomized controlled trial. J Am Dent Assoc 2021;152(11):903-08.
  15. Marinho VC, Higgins JP, Logan S, Sheiham A. Topical fluoride (toothpastes, mouthrinses, gels or varnishes) for preventing dental caries in children and adolescents. Cochrane Database Syst Rev 2003(4):CD002782.
  16. Hasson H, Ismail AI, Neiva G. Home-based chemically-induced whitening of teeth in adults. Cochrane Database Syst Rev 2006(4):CD006202.
  17. Torres CR, Perote LC, Gutierrez NC, Pucci CR, Borges AB. Efficacy of mouth rinses and toothpaste on tooth whitening. Oper Dent 2013;38(1):57-62.
  18. Kerr AR, Corby PM, Kalliontzi K, McGuire JA, Charles CA. Comparison of two mouthrinses in relation to salivary flow and perceived dryness. Oral Surg Oral Med Oral Pathol Oral Radiol 2015;119(1):59-64.
  19. Chi AC, Day TA, Neville BW. Oral cavity and oropharyngeal squamous cell carcinoma - an update. CA Cancer J Clin 2015;65(5):401-21.
  20. Weaver A, Fleming SM, Smith DB. Mouthwash and oral cancer: carcinogen or coincidence? J Oral Surg 1979;37(4):250-3.
  21. Gandini S, Negri E, Boffetta P, La Vecchia C, Boyle P. Mouthwash and oral cancer risk quantitative meta-analysis of epidemiologic studies. Ann Agric Environ Med 2012;19(2):173-80.

Last Updated: December 1, 2021

Prepared by:

Research Services and Scientific Information, ADA Library & Archives.