Co-codamol, a combination of paracetamol and codeine, takes up to 1 hour to start working to relieve pain, and its effects generally last for about 5 hours. Paracetamol works by blocking pain signals in the brain, while codeine acts on pain receptors in the central nervous system to further reduce pain. It is important to follow dosage instructions closely: adults typically take 1 to 2 tablets every 4 to 6 hours with a maximum of 8 tablets in 24 hours, and it should not be used for more than 3 days without consulting a healthcare professional. Overuse can cause serious side effects such as liver damage due to paracetamol and addiction risks from codeine. If pain persists beyond 3 days or the medication does not seem effective, one should seek medical advice.