Understanding xerostomia causes can help you work out what to do next. Medicines are a common contributor to dry mouth, but the symptom can have other causes too. Don’t stop or change a prescribed medicine on your own: a clinician or pharmacist can review your full medication list and discuss safer ways to manage symptoms.
Xerostomia causes: Which medicines can reduce saliva?
Xerostomia is the feeling of dry mouth; it does not always mean that tests would show low saliva flow. Many prescription and over-the-counter medicines can contribute, and the likelihood may rise when you take several medicines at once. Some reduce saliva through anticholinergic effects, which interfere with signals involved in salivary secretion.
Classes associated with dry mouth include antihistamines and decongestants, some antidepressants, medicines for overactive bladder, certain blood-pressure medicines and diuretics, and some pain medicines, muscle relaxants, antiseizure medicines and antispasmodics. This is not a complete list, and not everyone taking a medicine in one of these classes will develop symptoms. Check the patient information for your specific medicine, but ask a pharmacist or prescriber to help interpret it rather than assuming a medicine is the cause.
Dryness can be more noticeable at night: saliva production naturally falls during sleep, and mouth breathing may add to the problem. If you wake with a dry throat or mouth, note when it happens and whether it began after a medicine was started or its dose changed. That information can help guide a medication review.
Why a medication review is safer than stopping
A medicine that may be drying your mouth could also be treating an important condition. Your prescriber may be able to consider a different medicine, dose or schedule, but what is suitable depends on the drug and why you take it. A pharmacist can also check prescription medicines, non-prescription products and supplements for possible contributors. Bring a complete list, including medicines you take only occasionally, and describe when the dryness began.
Dry mouth can affect comfort and oral health, but it may be possible to ease symptoms while keeping necessary treatment in place. In a retrospective case series, Kayoko Ito and colleagues assessed 490 patients with medication-related dry mouth and objectively low saliva flow at the Xerostomia and Taste Disorder Clinic at Niigata University Medical and Dental Hospital in Japan. After six months of varied treatment, 75.3% reported improvement. The patients had been selected for care at a specialist clinic, and there was no untreated comparison group, so the result does not predict what will work for every person. It does show that symptom care can be considered alongside medication review.
Ways to ease dryness and protect your teeth
For short-term comfort, try frequent small sips of water or a saliva substitute or oral lubricant. Sugar-free gum may help stimulate saliva if you can chew comfortably. These measures can ease the sensation of dryness, but they do not identify its cause.
Saliva helps clean the mouth and protect teeth. When there is less of it, the risk of tooth decay, sensitivity and oral infections can rise. Brush gently at least twice a day with fluoride toothpaste, and keep up with dental check-ups. Tell your dentist about ongoing dry mouth; they can check for early tooth or gum problems and advise whether you need additional protection.
When persistent dry mouth needs assessment
Medicines are not the only possible explanation. Diabetes and Sjögren’s disease, an autoimmune condition that can affect moisture-producing glands, are among the other causes of dry mouth. Dehydration, some treatments for cancer and other health conditions can also contribute. A medication may be part of the picture without being the only cause.
Arrange an assessment with a clinician if dryness persists, is worsening, or makes it difficult to eat, swallow or speak. They can review your symptoms and medicines and decide whether to investigate another cause. Seek dental advice if you notice new tooth problems, mouth soreness or repeated oral infections. Do not try to diagnose the cause from dry mouth alone; a clinician can assess it in the context of your health and treatment.
