Constipation Flashcards
What is constipation?
Defaecation that is unsatisfactory because of infrequent stools, difficulty passing, or sensation of incomplete emptying of the rectum. Often defined as passage of stools less frequent than the person’s normal pattern.
What is the diagnostic criteria for constipation?
- spontaneous bowerl movements occurring less than 3 times per week
- stools often dry, hard, or lumpy and may be abnormally large or small
What is chronic constipation?
symptoms present for at least 12 weeks in preceding six months
What are some causes of constipation?
- poor fibre or fluid intake
- lack of exercise or reduced mobility
- pregnancy
- ignoring urge to go the toilet
- drugs
- stress, anxiety or depression
- symptoms of disease
- chronic GI disease
- age
What are some non-drug treatments of constipation?
- dietary changes
- improve toilet routine
- increasing activity
What are some drug treatments for constipation?
-bulk forming laxatives
- stimulant laxatives
- osmotic laxatives
- faecal softeners
How do bulk forming laxatives work?
Add bulk to stool and absorb water in intestine, increase faecal mass and stimulate peristalsis. Can take up to 72 hours to work and must be taken with plenty of water to avoid intestinal obstruction. Not taken at bedtime. Ispaghula husk, methylcellulose, and sterculia.
How do stimulant laxatives work?
increase peristalsis by directly stimulating muscles in lining of intestines. Can cause abdominal cramps. Take about 8 hours, advised to take at bedtime. Long-term use can cause dependence. They have limits on pack sizes, no longer used in children under 12, safety warnings about potential harm they may cause. Bisacodyl, sodium picosulphate, senna, co-danthramer, and co-danthrusate. Co-danthramer and co-danthrusate limited to constipation in terminally ill patients due to concerns about carcinogenicity and evidence of genotoxicity
How do osmotic laxatives work?
Increase amount of water in large bowel. Can take up to 48 hours to work, need good fluid intake. Lactulose, macrogols, and phosphate enemas. Phosphate enemas produce rapid results (15 mins). Used in severe constipation, causes faecal impaction and to clear bowel before surgical procedure. Not used as regular treatment.
How do faecal softeners work?
Reduce surface tension of faeces, allowing more liquid to penetrate faecal mass. Both softens the faeces, and increase faecal mass which stimulates peristalsis. Docusate, glycerol suppositories and arachis oil enemas. Docusate orally takes up to 48 hours. Rectal takes 15-20 minutes. Arachis oil contra-indicated in people with peanut allergy.
