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Constipation is defined as the passage of faeces (which may be hard) infrequently and with difficulty. It is a common enough problem in the general population but is even more prevalent in cancer patients for a variety of reasons, including:
Inactivity or immobility;
A poor diet with insufficient fibre or fluids;
Unfamiliar environment e.g. having to use a bedpan in the ward.
Many drugs can contribute to constipation. The most well known group is opioid analgesics, but chemotherapeutic agents like vincristine, vinblastine and venorelbine, and anti-emetics such as ondansetron, may also cause constipation.
Managing Constipation
A healthy balanced diet with sufficient fluids, and regular exercise, are a good first step. However many cancer patients will need extra help to maintain bowel regularity. Laxatives (from the Latin laxativus, loosening) come in a variety of preparations, most of which are available over the counter without prescription. An understanding of how laxatives work, will guide the choice of which to use.
Simply put, laxatives can be classified into
1.
Bulking Agents
2.
Softeners
3.
Flushers
4.
Pushers
Most people will need a combination of a “softener” and a “pusher”. A bulking agent may not be so palatable and would have to be taken separately from other medications. “Flushers” can be quite dehydrating; lactulose in recommended doses is however well tolerated.
ClickHEREto see the medications that used to manage constipation.
