Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Although not all side effects are known, Florastor is thought to be likely safe for most people when used as directed for up to 15 months.
Common side effects may include:
gas, bloating; or
constipation.
This is not a complete list of side effects and others may occur. Call your healthcare provider for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
 Florastor side effects (more detail)
