What to use for constipation after MiraLAX (polyethylene glycol) and senna?

Management of Constipation After MiraLAX and Senna

For constipation that persists after MiraLAX (polyethylene glycol) and senna, bisacodyl should be added at 10-15 mg daily to three times daily with a goal of one non-forced bowel movement every 1-2 days. 1

Stepwise Approach After First-Line Agents Fail

• If MiraLAX (polyethylene glycol) and senna have been ineffective, consider adding bisacodyl 10-15 mg daily to TID as the next step in management 1
• For opioid-induced constipation that doesn't respond to traditional laxatives, peripheral opioid antagonists such as naldemedine, naloxegol, or methylnaltrexone are recommended 1
• Magnesium-based laxatives (magnesium hydroxide 30-60 mL daily-BID or magnesium citrate 8 oz daily) can be effective but should be used cautiously in patients with renal impairment due to risk of hypermagnesemia 1
• Lactulose 30-60 mL BID-QID can be added if other measures fail 1

Assessment Before Escalating Therapy

• Rule out impaction, especially if diarrhea accompanies constipation (overflow around impaction) 1
• Rule out obstruction through physical examination and consider abdominal x-ray or GI consultation if suspected 1
• Discontinue any non-essential constipating medications 1
• Treat other causes of constipation such as hypercalcemia, hypokalemia, hypothyroidism, or diabetes mellitus 1

Interventions for Severe or Refractory Constipation

• For impaction: administer glycerine suppository with or without mineral oil retention enema 1
• Consider bisacodyl suppository (one rectally daily-BID) for more direct stimulation of the rectum 1
• For opioid-induced constipation, consider methylnaltrexone 0.15 mg/kg subcutaneously every other day (no more than once daily) except in cases of post-operative ileus or mechanical bowel obstruction 1
• Tap water enemas until clear may be necessary for severe impaction 1
• Consider use of a prokinetic agent such as metoclopramide 10-20 mg PO QID 1

Evidence for Different Laxative Classes

• Stimulant laxatives like bisacodyl and sodium picosulfate have moderate evidence supporting their use as second-line agents 2
• Polyethylene glycol solutions are emerging as an effective and safe mode of treatment for chronic constipation with good evidence supporting their use 3, 2
• Bulk laxatives such as psyllium are not recommended for opioid-induced constipation 1 but have moderate evidence supporting their use in other forms of constipation 2
• Recent systematic reviews provide good evidence (grade A recommendation) for both polyethylene glycol and senna, supporting their continued use in combination therapy 2

Special Considerations

• Avoid bulk laxatives like psyllium in opioid-induced constipation 1
• For patients with advanced disease and limited life expectancy, consider increasing the dose of stimulant laxatives with stool softeners (senna with docusate, 2-3 tablets BID-TID) 1
• Enemas are contraindicated for patients with neutropenia, thrombocytopenia, paralytic ileus, intestinal obstruction, recent colorectal or gynecological surgery, recent anal or rectal trauma, severe colitis, or undiagnosed abdominal pain 1
• Linaclotide may be considered for chronic idiopathic constipation in adults, as FDA-approved data shows significant improvement in spontaneous bowel movement frequency 4

Remember that the goal of therapy is one non-forced bowel movement every 1-2 days, and treatment should be adjusted accordingly to achieve this outcome while minimizing side effects.