Home oral hygiene is probably the most effective way to reduce accumulations of debris and bacteria that lead to halitosis. This includes regular tooth brushing and flossing, and/or the use of mechanical irrigators to remove accumulations of food after eating. Brushing the tongue or using a commercial tongue scraper, especially over the bumpiest region of the tongue, may help remove the odour-causing agents as well as lower the overall bacteria count in the mouth.

Because of the role of gum disease in halitosis, regular dental care is recommended to prevent or treat gum disease. Treatment for a person with periodontal pockets might include scaling of the teeth to remove tartar.¹⁹

A reduced saliva flow increases the concentration of bacteria in the mouth and worsens bad breath.²⁰ One of the most common causes of dry mouth is medication, such as antihistamines, some antidepressants, and diuretics; however, chronic mouth breathing, radiation therapy, dehydration, and various diseases can also contribute.²¹ Measures that help increase saliva production (e.g., chewing sugarless gum and drinking adequate water) may improve halitosis associated with poor saliva flow. Avoiding alcohol (ironically found in many commercial mouthwashes) may also help, because alcohol is drying to the mouth.

Access by oral bacteria to sulphur-containing amino acids will enhance the production of sulphur gases that are responsible for bad breath. This effect was demonstrated in a study in which concentrations of these sulphur gases in the mouth were increased after subjects used a mouth rinse containing the amino acid cysteine.²² Cleaning the mouth after eating sulphur-rich foods, such as dairy, fish, and meat, may help remove the food sources for these bacteria.