Human: What are the side effects of taking ibuprofen? Assistant: 
The most common side effects of taking ibuprofen include upset stomach, heartburn, nausea, dizziness, headache, and rash. Less common but more serious side effects include stomach ulcers, allergic reactions, and insomnia. In rare cases, ibuprofen may also cause liver or kidney damage. It is important to follow your doctor’s instructions for taking ibuprofen or any other nonsteroidal anti-inflammatory drug (NSAID).