Look for any of the following signs and symptoms of fecal impaction: absence of bowel movements, a sensation of fullness in the rectum, distention in the abdomen or abdominal discomfort, loss of urinary control, a firm mass in the lower left abdomen, watery stools or discharge from the rectum.
Drink copious amounts of water and avoid starch and meats.
Eat plenty of fruits, leafy vegetables, bran and high-fiber cereals. Dried fruits such as apricots, dates and prunes are a great way to get fiber while backpacking.
Administer a stool softener, laxative, or milk of magnesia.
Administer a glycerin suppository to encourage passage of the stool and to prevent the hardened stool from damaging the rectal lining. If a glycerin suppository is unavailable in the field you may have to improvise an enema using mineral oil.
Digitally remove the stool with the following steps if none of the above measures successfully evacuates the stool.
Put on a latex glove and administer an enema of glycerin or mineral oil. Lubricate the latex glove and insert the index finger into the rectum and gently locate the mass of stool.
Break up the mass of stool piece by piece with gentle prodding, taking care not to damage to the rectal lining. Attempt to eliminate the pieces on a piece-by-piece basis using a glycerin suppository.
Evacuate the person if the impacted stool can't be located with a gloved finger, if digital probing fails to eliminate the stool, if a fever is present, or if the rectal lining is at all damaged in the removal process.