What are common side effects of benzonatate?

Common benzonatate side effects include dizziness, drowsiness, and headache. Constipation and nausea can happen, too. Most side effects are generally mild, can be managed at home, and go away when you stop taking benzonatate. Serious benzonatate side effects are rare but can include severe drowsiness, confusion, and hallucinations. In children under 10 years old, too much benzonatate can be fatal. Discuss these risks with a healthcare professional before taking benzonatate.  View original source