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I have always been regular but am now taking co-codamol for arthritis in my spine.
It controls the back pain and allows me to keep active, but since starting the medication I have been struggling to go to the loo, despite eating lots of fruit and veg, having bran for breakfast and even adding in fibre supplements (Fybogel) from the pharmacy.
There is only so much fibre I can eat!
Co-codamol is a mix of paracetamol and codeine, and it is the latter that is likely to be blocking you up. There is a good reason that opioid drugs like codeine have long been a popular remedy for diarrhoea: they are very effective at slowing the bowel.
Fibre, the indigestible component of foods such as fruit, veg and cereals, enables the bowel to work smoothly because it traps water, helping to keep everything soft and moving. However, for it to help as intended you do need to ensure that you are drinking enough, particularly during warmer spells. If you don’t, the body absorbs the extra water it needs from your colon, making stools firmer and harder to pass.
In general, increasing fibre and fluid intake should always be the first step in tackling constipation, but if it is caused by opioids such as codeine, extra help is often required. And rather than further boosting fibre intake with products like Fybogel – which can, paradoxically, make people with opioid-induced constipation more uncomfortable – it is better to add in a laxative, or even two.
The first choices are either a stimulant such as senna, a softener/water retainer like macrogol (for example, Laxido or Movicol), or both.
In other causes of constipation, GPs tend to start with the macrogol, but in someone taking codeine or other opioids, we normally try senna first, as it helps speed up a sluggish bowel. Both are available without prescription, though your doctor can prescribe them if required.
Have you got a medical question for Dr Mark Porter? He can’t reply individually, but will respond to questions on this page*
Email drmark@saga.co.uk.
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