NRG Management of Constipation Version 1.0
Goal: Develop an evidence-based template for the management of constipation.
Practical Considerations
 Remember to review the protocol for any prohibited medications as some medications may be
prohibited due to drug interactions
 Supportive care should follow institutional standards when permitted per the protocol
 Local complications from constipation may include fecal impaction, overflow diarrhea, gastrointestinal
obstruction or perforation, hemorrhoids, rectal prolapse, and anal tears or rectal bleeding
 Additional complications may include halitosis, early satiety, nausea and vomiting, and gastroesophageal
reflux
 Consider and address possible causes of functional constipation
o Positive family history
o Low levels of dietary fiber or poor food and fluid intake
o Low levels of physical activity
o Lack of privacy, need for assistance during toileting
 Consider causes of secondary constipation and modify therapy as indicated
o Opioid-induced
o Other medications (e.g., antacids, diuretics, anti-emetics, anticholinergics, iron supplements,
vinca alkaloids)
o Metabolic problems (e.g., dehydration, hypercalcemia, hypokalemia, hypothyroidism, diabetes)
o Neurological or psychiatric diseases (e.g., dementia, depression)
o Gastrointestinal diseases (e.g., diverticulosis, irritable bowel syndrome)
o Structural issues (e.g., abdominal or pelvic mass, radiation fibrosis, peritoneal carcinomatosis)
 Opioid-induced constipation
o All patients prescribed an opioid should be started on concomitant laxative therapy, unless
contraindicated by pre-existing diarrhea
o Osmotic or stimulant laxatives are preferred
o Bulk laxatives such as psyllium are not recommended
o If unresolved with conventional laxatives, peripheral opioid antagonists (methylnaltrexone or
naloxegol) may be of value
 Titrate to a bowel movement every 1-2 days (or the patient’s baseline)
Therapeutic Approach to Constipation in Patients with Cancer
Preventative Measures
 Set goals of treatment and explain to patient and family (soft stools, ease of defecation, bowel
movement every 1-2 days, adjusted per individual bowel habits)
 Patients taking daily opioids almost always require agents for management of constipation
 Prophylactic medications
o Stimulant laxative (e.g., senna 2 tablets daily; maximum 8 tablets per day)
o Osmotic laxative (e.g., polyethylene glycol 17 grams = 1 heaping tablespoon in 8 oz of water PO
1-2 times daily
o May need to increase dose of laxative when increasing dose of opioids
 Maintain adequate fluid intake
 While maintaining adequate dietary fiber is recommended, supplemental medicinal fiber (e.g. psyllium)
is unlikely to control opioid-induced constipation and may worsen constipation
 Exercise, if tolerated
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Constipation Treatment
 Assess for cause and severity of constipation, including impact or other contributing medications
 Rule out obstruction
 Titrate laxatives as needed with a goal of one non-forced bowel movement every 1 to 2 days
o Stimulant laxative (e.g., senna 2 tablets daily; maximum 8 tablets per day) and/or
o Osmotic laxative (e.g., polyethylene glycol 17 grams dissolved in 4-8 oz of beverage PO 1-2
times daily)
 If senna and polyethylene glycol have not relieved constipation, consider adding another agent
o Magnesium hydroxide
o Bisacodyl orally or rectally (avoid rectal route in neutropenic or thrombocytopenic patients)
o Lactulose
o Magnesium citrate
 If response to laxative therapy has not been sufficient for opioid-induced constipation, consider
peripherally acting mu-opioid receptor antagonists (PAMORAs) such as methylnaltrexone, naloxegol, or
naldemedine
o These agents should not be used in patients with known or suspected mechanical bowel
obstruction, recent bowel surgery, transmural bowel metastases, or other processes affecting
integrity of GI lumen due to potential increased risk of perforation
 Bulk laxatives are not preferred in patients with cancer as they require fluid volume and impact wanes
over time
 Increase activity and mobility, within patient limits
 In general, enemas are only used if oral treatment fails after several days and in order to prevent fecal
impaction
 Contraindications for enema use
o Neutropenia or thrombocytopenia
o Paralytic ileus or intestinal obstruction
o Recent colorectal or gynecological surgery
o Recent anal or rectal trauma
o Severe colitis, inflammation, or infection of the abdomen
o Toxic megacolon
o Undiagnosed abdominal pain
o Recent radiotherapy to the pelvic area
References
 Davies A, Leach C, Caponero R, et al. MASCC recommendations on the management of constipation in
patients with advanced cancer. Support Care Cancer 2020; 28(1): 23-33.
 Larkin PJ, Cherny NI, La Carpia D, et al. Diagnosis, assessment and management of constipation in
advanced cancer: ESMO Clinical Practice Guidelines. Ann Oncol 2018; 29: iv111-iv125.
 National Comprehensive Cancer Network. Adult Cancer Pain (Version 1.2021). Available from:
https://www.nccn.org/professionals/physician_gls/pdf/pain.pdf.
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Senna
Bisacodyl
Polyethylene glycol
(PEG)
Lactulose
Magnesium hydroxide
Magnesium citrate
Methylnaltrexone
Naloxegol
Drug Specific Considerations
Stimulant Laxatives
Oral, tablet (8.6 mg sennosides)
Best taken in the evening or at bedtime
8.6 mg sennosides/tablet: 2 tablets
with the aim of producing a normal
daily; maximum 4 tablets twice daily
stool next morning
Oral, syrup (8.8 mg sennosides/5 mL)
8.8 mg/5 mL syrup: 10 to 15 mL once
daily; maximum 15 mL twice daily
Oral, tablet (5 mg)
5 to 15 mg once daily
Rectal, suppository or enema (10 mg)
10 mg (1 suppository or enema) once
daily
Osmotic Laxatives
Oral, powder or packet (17 g/dose)
17 mg (~1 heaping tablespoon)
dissolved in 120 to 240 mL (4-8 oz) of
beverage once to twice daily
Oral, solution (10 g/15 mL)
10 to 20 grams (15 to 30 mL) daily
May increase to 40 grams (60 mL) daily
Oral, suspension (milk of magnesia)
Magnesium hydroxide 400 mg/5 mL
30 to 60 mL once daily or in divided
doses
Magnesium hydroxide 800 mg/5 mL
15 to 30 mL once daily or in divided
doses
Magnesium hydroxide 1,200 mg/5 mL
10 to 20 mL once daily or in divided
doses
Oral, solution
195 to 300 mL given once or in divided
doses
Opioid Receptor Antagonists
SubQ
<38 kg: 0.15 mg/kg
38 to <62 kg: 8 mg
62 to 114 kg: 12 mg
>114 kg: 0.15 mg/kg
Oral, tablet (12.5 mg, 25 mg)
25 mg once daily, may reduce to 12.5
mg once daily if not tolerated
Titrate to effect with a maximum dose
of 4 tablets twice daily
Suppositories/enemas are
contraindicated for patients who are
neutropenic or thrombocytopenic
Virtually no net gain or loss of sodium
and potassium
Not absorbed by the small bowel
Takes 2-3 days before onset
Use cautiously in renal impairment
Excessive doses of oral magnesium salts
can lead to hypermagnesemia
Best taken at bedtime with the aim of
producing a normal stool next morning
Use cautiously in renal impairment
Accumulation of magnesium may lead
to magnesium intoxication
FDA approved for opioid-induced
constipation in adults with advanced
illness who are receiving palliative care
FDA approved for opioid-induced
constipation in adults with chronic
noncancer pain
Discontinue all maintenance laxative
therapy prior to use and reintroduce, as
needed after 3 days
Significant drug interactions exist
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Naldemedine
Oral, tablet (0.2 mg)
0.2 mg once daily
FDA approved for opioid-induced
constipation in adults with chronic
noncancer pain
Significant drug interactions exist