Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have:
confusion, hallucinations;
severe dizziness or drowsiness; or
little or no urinating.
Common side effects may include:
blurred vision;
dry mouth, nose, or throat;
constipation; or
mild dizziness or drowsiness.
Side effects such as dry mouth, constipation, and confusion may be more likely in older adults.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
 Unisom SleepTabs side effects (more detail)
