Can bisoprolol (beta-blocker) cause dry mouth?

Bisoprolol and Dry Mouth

Yes, bisoprolol can cause dry mouth as a side effect, though it is not among its most common adverse reactions.

Evidence for Bisoprolol and Dry Mouth

• The FDA drug label for bisoprolol specifically lists dry mouth as an adverse reaction occurring in approximately 1.5% of patients taking bisoprolol at doses of 5-20 mg, compared to 0.7% in placebo groups 1
• Dry mouth is categorized under "Autonomic Nervous System" adverse effects in the official bisoprolol prescribing information 1
• Beta-blockers as a class have been documented to potentially affect salivary gland function, with studies showing that beta-adrenoceptor antagonists can affect salivary composition 2

Mechanism and Comparison with Other Medications

• While bisoprolol is a beta-1 selective adrenoceptor antagonist, it still has some effects on the autonomic nervous system that can lead to dry mouth 1, 3
• Alpha-adrenergic blockers, which are sometimes used in cardiovascular treatment, are more prominently noted to cause dry mouth as a side effect 4
• Anticholinergic medications typically cause more significant and frequent dry mouth compared to beta-blockers like bisoprolol 5, 6

Clinical Significance and Management

• Dry mouth from bisoprolol is generally mild and occurs in a relatively small percentage of patients (1.5%) 1
• For patients experiencing dry mouth while on bisoprolol, the following strategies may help:
  • Maintaining adequate hydration 5
  • Using saliva substitutes and mouth rinses 4
  • Chewing sugarless gum or candy to stimulate saliva production 5
  • Good oral hygiene to prevent dental complications 4

Important Considerations

• Polypharmacy significantly increases the risk of dry mouth, so reviewing the patient's complete medication list is important 5, 2
• If dry mouth is severe and persistent, consider:
  • Evaluating for alternative beta-blockers if appropriate 4
  • Consulting with a dentist if oral complications develop 4
  • Recognizing that severe sicca syndrome, if left untreated, can result in dental caries and tooth loss 4

Comparative Incidence

• The 1.5% incidence of dry mouth with bisoprolol is relatively low compared to medications with stronger anticholinergic properties 1, 6
• A comprehensive review of medications affecting salivary gland function identified beta-blockers as having moderate evidence for causing dry mouth, but at lower rates than many other medication classes 6