From the Guidelines
For severe constipation treatment, the most effective approach is to start with lifestyle modifications and then progress to pharmacological interventions, with the goal of minimizing morbidity, mortality, and improving quality of life, as recommended by the American Gastroenterological Association and the American College of Gastroenterology 1.
Initial Management
The initial management of severe constipation should include lifestyle modifications such as:
- Increased fluid intake (at least 8 glasses of water daily)
- More dietary fiber (25-30g daily)
- Regular physical activity
Pharmacological Interventions
Over-the-counter options include:
- Osmotic laxatives like polyethylene glycol (MiraLAX, 17g in 8oz water daily for up to 7 days) 1
- Stimulant laxatives such as bisacodyl (Dulcolax, 5-10mg orally) for short-term relief
For persistent cases, consider prescription medications like:
- Lubiprostone (Amitiza, 24mcg twice daily)
- Linaclotide (Linzess, 145-290mcg once daily) 1
Additional Interventions
Manual disimpaction may be necessary for fecal impaction, performed by a healthcare provider. Enemas can provide rapid relief - phosphate enemas work within 5-15 minutes. Severe cases unresponsive to these treatments require medical evaluation as they may indicate underlying conditions like bowel obstruction or neurological disorders.
These treatments work through different mechanisms - osmotic laxatives draw water into the bowel, stimulants increase intestinal contractions, while prescription medications enhance intestinal fluid secretion and motility. It is essential to note that the management of severe constipation should be individualized, and the choice of treatment should be based on the patient's specific needs and medical history, as well as the potential risks and benefits of each treatment option 1.
From the FDA Drug Label
RELISTOR tablets and RELISTOR injection are indicated for the treatment of opioid-induced constipation (OIC) in adults with chronic non-cancer pain, including patients with chronic pain related to prior cancer or its treatment who do not require frequent (e.g., weekly) opioid dosage escalation. RELISTOR injection is indicated for the treatment of OIC in adults with advanced illness or pain caused by active cancer who require opioid dosage escalation for palliative care.
The treatment for severe constipation with methylnaltrexone (PO) is indicated for opioid-induced constipation (OIC) in adults with:
- Chronic non-cancer pain
- Advanced illness or pain caused by active cancer The recommended dosage is:
- 450 mg once daily for RELISTOR tablets in adult patients with chronic non-cancer pain
- 12 mg subcutaneously once daily for RELISTOR injection in adult patients with chronic non-cancer pain
- 8 mg or 12 mg subcutaneously every other day for RELISTOR injection in adult patients with advanced illness 2
From the Research
Treatment Options for Severe Constipation
- Laxatives and stool softeners are commonly used to treat opioid-induced constipation (OIC) 3
- Newer agents have been introduced to the market, broadening options for patients who do not respond to first-line therapies 3
- A high-fiber diet and fluid supplementation can increase stool frequency and decrease laxative use in patients with functional constipation 4
- Polyethylene Glycol (PEG) is more effective than lactulose in treating chronic constipation, with better outcomes in stool frequency, stool form, and relief of abdominal pain 5
- Bisacodyl, a stimulant laxative, has a dual prokinetic and secretory action and can be used to treat constipation, with similar efficacy to other laxatives 6
Pharmacologic Treatments for Constipation
- Senna, docusate, bisacodyl, polyethylene glycol 3350, and lactulose are commonly used preparations for the treatment of OIC 3
- Osmotic laxatives, such as PEG 3350 and lactulose, are effective and safe for both long and short term treatment of pediatric functional constipation 7
- Stimulant laxatives, like Senna and Bisacodyl, can be used as adjunct therapies in specific clinical scenarios 7
- Probiotics, fiber preparations, enemas, and suppositories are also available as over the counter agents for the treatment of pediatric constipation 7