Paracetamol and codeine

Dose

The pharmacy label on your medicine will tell you how much to take, how often to take it and any special instructions.

• The usual dose of paracetamol and codeine is 1 or 2 tablets every 4 to 6 hours when needed for pain. Do not take more than 8 tablets in 24 hours.
• You may need to take less than this if you are frail or elderly, or have problems with your liver.
• Taking too much paracetamol can cause liver failure.
• Talk to your doctor or pharmacist about the best dose for you if you are unsure.

Different people respond to codeine differently

Codeine is broken down in your liver to morphine, which is a strong pain reliever. People may respond differently to codeine depending on how their liver breaks down codeine.

• Some people break down codeine very slowly (called poor metabolisers), which means that they are unable to convert codeine to morphine, and don't get enough pain relief.
• Some other people break down codeine very quickly (called ultra-rapid metabolisers) and are at increased risk of developing side effects, even at low doses.
• Estimates suggest that up to 10% of the European//Pākehā  population may be poor or ultra-rapid metabolisers. The prevalence in Māori and Pacific Peoples is not known.
• If you are taking codeine for pain relief, and it doesn’t seem to be working, let your doctor know. 
• If you are taking codeine and you get side effects such as nausea, vomiting, constipation, lack of appetite, drowsiness or extreme sleepiness, let your doctor know. Other options may be better for you.
• If you have more severe side effects, such as difficulty waking, confusion or shallow breathing, let your doctor know straight away or call Healthline 0800 611 116.

How to take paracetamol and codeine

• Swallow your tablets whole with a drink of water.
• You can take paracetamol and codeine with or without food.

Here are some things to know when you're taking paracetamol and codeine. Other things may be important as well, so ask your healthcare provider what you should know about.

• Taking too much of paracetamol can be harmful to your liver. Paracetamol is contained in many other pain relief and cold and flu medicines. Check the ingredients of pain relief medicines and cold and flu medicines before you take them. Check with your pharmacist if you are not sure whether a product contains paracetamol. Read more about the safe use of paracetamol.  
• Paracetamol and codeine can affect your ability to do tasks such as driving or using tools or machines. Limit or avoid drinking alcohol while you are taking paracetamol and codeine. Alcohol makes this worse. Before engaging in these activities, discuss your risk with your health professional.  
• Paracetamol and codeine can interact with other medicines. Tell your doctor or pharmacist about all medicines you are taking including over the counter medicines and herbal or complementary medicines. 
• It's possible to become addicted to the codeine in paracetamol and codeine with long-term use. Take the lowest dose for the shortest time Do not take high doses of the medicine for long periods of time.

Like all medicines, paracetamol and codeine can cause side effects, although not everyone gets them. Often side effects improve as your body gets used to the new medicine.