Antihistamines are medications used to treat allergies. They’re associated with several side effects, including bad breath.
In most cases, bad breath (halitosis) isn’t a cause for concern. In fact, it’s normal to have stinky breath every now and then. However, if you regularly take antihistamines, you might be concerned about this side effect.
In this article, we’ll explain why antihistamines cause bad breath. We’ll also explore additional causes of bad breath, including foods, habits, and other medications.
Bad breath is caused by the overgrowth of certain bacteria in the mouth.
This can happen for many reasons:
- Poor oral hygiene. Oral hygiene involves brushing and flossing your teeth, which controls odor-causing bacteria. Failing to practice good oral hygiene can lead to bacterial overgrowth.
- Dry mouth. Saliva naturally washes away odor-causing bacteria, as well as the acids they produce. A dry mouth can lead to bacterial overgrowth.
- Certain foods. Some foods, like coffee, onions, and garlic, can lead to bad breath.
- Smoking tobacco. The chemicals in cigarette smoke can make the bacteria in your mouth unbalanced. This includes the overgrowth of odor-causing bacteria.
- Medications. Bad breath is a side effect of many medications, including antihistamines.
- Gum disease. Gum disease, or gingivitis, is caused by a bacterial infection in the gums. In its advanced stages, gum disease can cause bad breath from plaque build-up.
- Other medical conditions. Many conditions, like diabetes, gastric reflux, and liver or kidney disease, can also lead to bad-smelling breath.
You might be more likely to experience bad breath if multiple factors apply to you.
Antihistamines are medications that treat allergic reactions. They work by reducing levels of histamine, a chemical that causes allergy symptoms.
However, antihistamines also have anticholinergic effects. This means they block the action of acetylcholine, a neurotransmitter. Neurotransmitters are chemical messengers released by nerve cells.
Acetylcholine is involved in normal saliva function and flow. Saliva is needed to wash away bacteria, including those that cause bad breath. It also washes away food and debris, which the bacteria feed on.
However, the anticholinergic effect of antihistamines blocks acetylcholine, decreasing salivary flow. This increases dry mouth, resulting in bad breath.
But this side effect isn’t specific to antihistamines. Many other medications can also cause bad breath, such as:
- anticholinergics (used for urinary incontinence, heart disease, and more)
- dietary supplements
- acid reducers
- chemotherapeutic agents
It’s possible to control bad breath using home remedies and certain habits. This includes managing the effects of antihistamines and increasing moisture in the mouth.
Home remedies to try include:
- Sip water often. Sipping water, especially while eating, will increase the moisture in your mouth. You can also sip on sugarless drinks, such as herbal tea without sugar.
- Chew on sugarless gum. Chewing gum can help promote saliva production. Another option is to suck on sugarless hard candies.
- Use a humidifier. A humidifier is a device that adds moisture to the air. This can help moisturize your mouth, potentially reducing dryness and bad breath.
- Use products that moisten the mouth. Artificial saliva products and oral rinses can increase moisture in the mouth. Be sure to use an oral rinse without alcohol, which has a drying effect.
- Avoid cigarette smoking. The habit can dry out the mouth, which can worsen the side effects of antihistamines. Cigarette smoking also increases the production of odor-causing bacteria.
- Limit or avoid alcohol. Drinking alcohol can lead to dry mouth and bacterial overgrowth.
- Practice good oral hygiene. Brush your teeth at least twice a day, and again after eating very sugary and sticky foods. Floss your teeth regularly.
Additionally, only use antihistamines as directed by your doctor. Avoid taking them more than you need to.
If you’re concerned about bad breath due to antihistamines, talk to your doctor. They might be able to provide guidance or alternatives.
Also, visit a doctor if you notice any of the following symptoms:
- persisting bad breath for several weeks, even with home remedies
- symptoms of a respiratory infection, such as fever or coughing
- gum pain
- bleeding or swollen gums
- denture problems
Bad breath is a common side effect of taking antihistamines. That’s because antihistamines block acetylcholine, a neurotransmitter involved in saliva production. This reduces salivary flow, resulting in dry mouth.
When your mouth is dry, it’s easier for odor-causing bacteria to grow. The result is bad breath. However, habits like sipping on water, using a humidifier, and chewing on sugarless gum can help.
If your bad breath doesn’t go away with home remedies, see a doctor. You should also seek medical help if you have a fever, toothache, or bleeding gums, which might indicate more serious conditions.