Question: how long can you take painkillers for?
Answer: For some types of long-term pain, you'll need to take ibuprofen regularly for up to 3 weeks for it to work properly. If you're applying ibuprofen to your skin, it should start to work within 1 to 2 days. Is ibuprofen better than paracetamol or aspirin? Ibuprofen, paracetamol and aspirin are all effective painkillers.