Childrens above twelve years old can take it if other regular pain killers did not work. It is not suitable for some people like those who are allergic to codeine, kidney problem, liver problem, addicted to alcohol, low blood pressure, lung problem, trying to be pregnant or during pregnancy or breastfeeding. Codeine is a pain relieving medication and also it helps to treat cough and flu. It will also relieve anxiety and stress which are caused by pain in an individual. As it relieves pain it also has some side effects such as headache, dizziness, drowsiness, and slow breathing. It works within thirty to sixty minutes of taking it. Firstly you have to consult your doctor about taking any kind of pain relief medicine and they will supervise you during the period of you taking codeine.