Laxatives (cancer treatment)
Laxatives, also known as bowel stimulants, are substances that promote bowel movements and can be crucial for cancer patients who frequently experience constipation due to various factors, including treatment side effects. Nearly 60% of cancer patients suffer from constipation, often caused by reduced mobility, pain medications, decreased fluid intake, or chemotherapy effects. There are several classes of laxatives, including bulk-producing agents, stool softeners, lubricants, hydrating agents, and stimulants, each with distinct mechanisms of action.
Bulk-producing agents, like psyllium husk and dietary fiber, enhance stool mass and stimulate intestinal movement, while stool softeners, such as docusate, help make stools easier to pass. Lubricants, like mineral oil, facilitate stool passage, though they may impair absorption of fat-soluble vitamins. Hydrating agents, including milk of magnesia, draw water into the colon to soften stools rapidly. Stimulant laxatives, such as cascara and senna, induce bowel movement but are generally not recommended as a first-line treatment due to their potency and potential side effects.
Side effects of laxatives can include diarrhea, dependency, and potential interactions with other medications, making it essential for cancer patients to consult healthcare providers before use. Current research also indicates that while non-fiber laxatives might increase colorectal cancer risk, high-fiber options could potentially lower this risk, though further studies are needed.
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Laxatives (cancer treatment)
ALSO KNOWN AS: Bowel stimulants
DEFINITION: Laxatives are drugs, food, or compounds that promote a bowel movement. They can be used to prepare the bowel for diagnostic examination or to prevent or treat constipation.
Cancers treated: All
Subclasses of this group: Bulk-producing agents, stool softeners, lubricants and emollients, hydrating agents, stimulants
Delivery routes: Laxatives are taken orally or in a suppository form.
Description: According to a study published in the Journal of the Advanced Practitioner in Oncology, nearly 60 percent of cancer patients experience constipation. Cancer patients experience constipation for various reasons. Cancer treatments may render patients less active or mobile, which increases the risk of constipation. Depression or anxiety as a result of cancer treatments or pain can also result in constipation. Repeated use of pain medications, decreased intake of fluids, or chemotherapy may lead to constipation in cancer patients. Intestinal tumors or scar tissue from intestinal surgeries for cancer can have an impact on the body’s ability to empty waste material.
How these agents work: Laxatives work in diverse ways. Bulk-producing agents combine with water to increase the mass of the stool and stimulate the intestinal muscles. Common bulk-producing laxatives include psyllium husk, dietary fiber, and apples. These gentle agents enhance peristalsis within twelve to seventy-two hours.
Stool softeners or surfactants also produce bowel movements in twelve to seventy-two hours. By drawing water into the stool, these laxatives soften the stool, which is useful for cancer patients who experience pain when passing a firm stool. Stool softeners can build a tolerance, however, making the laxative ineffective for some cancer patients. Docusate (Colace) is a stool softener.
Lubricants or emollients make the stool slippery and act in the colon within six to eight hours. They work by making the stool slide more easily through the colon. An example of a lubricant laxative is mineral oil. One concern is that mineral oil can cause decreased absorption of the fat-soluble vitamins, such as A, D, E, and K.
Hydrating agents or osmotics are laxatives that draw water into the colon to soften the stool. These laxatives produce desired results within thirty minutes to six hours. Examples of hyperosmotic laxatives include milk of magnesia (magnesium hydroxide), Epsom salts (magnesium sulfate), and glycerin suppositories. GoLYTELY, a solution of polyethylene glycol (PEG) 3350 and electrolytes, is often used as a preparatory agent for colon procedures such as colonoscopy.
Another form of laxative is a stimulant or irritant, such as cascara, senna, aloe vera, biscodyl (Ducolax), or castor oil. These agents stimulate movement in the colon and are the most severe of all laxatives; they should not be the cancer patient’s laxative of choice.
Side effects: The side effects of laxatives may include diarrhea and dependency. Overuse can result in the inability to have a bowel movement and lead to constipation or impaction. Because laxatives can lessen the effectiveness of some medications, a health care provider should be consulted before their use. A study published in the American Journal of Gastroenterology found that the use of non-fiber laxatives can increase the risk of colorectal cancer significantly, but high-fiber laxatives can reduce the risk. However, more research is needed on the topic before recommendations are made.
Bibliography
Aleccia, JoNel. “Bulk It Up: High-Fiber Laxatives Linked to Lower Colorectal Cancer Risk.” Fred Hutchinson Cancer Center, 8 Oct. 2014, www.fredhutch.org/en/news/center-news/2014/10/laxatives-colon-cancer-risk.html. Accessed 26 June 2024.
Avila, Jorge G. "Pharmacologic Treatment of Constipation in Cancer Patients." Cancer Control 11.3 suppl. 1 (2004): 10–18. Print.
Citronberg, Jessica, et al. "A Prospective Study of the Effect of Bowel Movement Frequency, Constipation, and Laxative Use on Colorectal Cancer Risk." American Journal of Gastroenterology 109.10 (2014): 1640–49. Print.
"Constipation." National Cancer Institute. Natl. Institutes of Health, 28 Aug. 2014. Web. 29 Oct. 2014.
"Laxatives." Cancer Research UK. Cancer Research UK, 21 May 2014. Web. 29 Oct. 2014.
Wickham, Rita J. “Managing Constipation in Adults with Cancer.” Journal of the Advanced Practitioner in Oncology 8.2 (2017): 149-161. www.ncbi.nlm.nih.gov/pmc/articles/PMC5995490/. Accessed 26 June 2024.
Wirz, S., et al. "Laxative Management in Ambulatory Cancer Patients on Opioid Therapy: A Prospective, Open-Label Investigation of Polyethylene Glycol, Sodium Picosulphate and Lactulose." European Journal of Cancer Care 21.1 (2012): 131–40. Print.