Managing side-effects of treatment
How do you walk the tightrope between analgesia and sedation?
If a patient needs analgesia but has intolerable side-effects at the necessary dosages, it may help to switch to a different opiate, so-called 'opiate rotation'.
What is your advice for GPs when prescribing for constipation caused by opiates?
There are three classes of laxatives the softeners and osmotic agents, stimulants, and bulking agents. Bulking agents are not useful in palliative care and are probably best regarded as bowel normalisers rather than laxatives. I tend to use liquid paraffin and magnesium hydroxide emulsion (Milpar, non-NHS) or docusate as softeners and senna or picosulphate elixir as stimulants. Co-danthramer and co-danthrusate are useful combination laxatives but they have licence limitations and should be restricted to those patients who have a malignant diagnosis.
What can be done for patients suffering from unpleasant mouth symptoms?
Many drugs cause dry mouth, especially morphine, which might be difficult to stop. Simple things can help such as treating thrush, chewing gum or eating pineapple chunks. Pilocarpine tablets can be very helpful in stimulating saliva production, but this drug has a lot of side-effects.
We are involved in a study on treating dry mouth using bethanechol, a muscarinic drug with a starting dose of 25mg tds that just stimulates the salivary glands. Theoretically, if you can keep saliva flowing you may reduce thrush as well.
For thrush we go straight to oral fluconazole as there is increasing resistance to nystatin. We start at fluconazole 50mg daily and increase to 100mg if there is not clearance.
When prescribing for a terminally ill patient on multiple drugs, can you afford to overlook drug interactions and relative contraindications?
It is important to minimise the risk of drug interaction by prescribing as few drugs as possible. Stop unnecessary drugs such as iron. Use slow-release preparations and alternative routes, where available, so fewer oral doses are needed.