Co-codamol 8/500 Effervescent Tablets Co-codamol 8/500 Effervescent Tablets treats acute moderate pain such as headache, migraine, toothache, period pain, muscular pains & back-ache. It contains two active ingredients: Codeine: This belongs to a group of medicines called opioid analgesics which act to relieve pain. Paracetamol: A painkiller that also reduces your temperature when you have a fever. Co-codamol 8/500 Effervescent Tablets are suitable for adults & children from 12 years of age but should only be used for a maximum of three days at a time & only for pain that is not relieved by other painkillers such as paracetamol or ibuprofen alone.