Last night I posted about laxatives and the over use of laxatives. Tonight I want to point out that salt-based or carbohydrate-based or “osmotic” laxatives that use natural salts, magnesium salts or undigested sugars to help loosen stool by drawing water through the bowel wall into the bowel. Some of the better examples include Milk of Magnesia, lactulose and Miralaxor polyethylene glycol.
Another type of laxative is a stimulant laxative. These include laxatives that happen to contain senna, cascara or bisacodyl. These laxatives are less gentle and cause the colon muscles to contract more frequently or more aggressively.
Laxatives come in a variety of forms such as those that can be taken orally and those that can be inserted into the rectum, like a suppository. Although not a laxative, an enema can relieve constipation, too.
Enemas are available at pharmacies and one does not need a prescription in order to buy one. According to the website http://www.drugs.com/health-guide/constipation-and-impaction.html, a traditional enema is done with a bag of liquid (usually a mixture of salt and water) attached to a plastic tube with a tapered tip. The enema fluid can be emptied into the rectum after the tip is inserted into the anus. The fluid is emptied when you lift the bag several inches and allow the fluid to move with gravity. An enema loosens stool in the rectum and triggers the rectal muscles to squeeze as a reaction to their being stretched.
Knowing which form of laxative for your client to use, or if they need an enema instead, is just another way to show your clients that With Age Comes Respect.
With Age Comes Respect - An Elderly Caregiver's Perspective 
Good information, thank you