Understanding Slow Transit Constipation (STC)
Slow transit constipation (STC) is a type of chronic idiopathic constipation (CIC) characterized by slow movement of stool through the colon. This is due to dysfunctional muscle contractions and neural signals, leading to infrequent and difficult bowel movements. Unlike other constipation types responsive to fiber or osmotic laxatives, STC often requires prescription medications targeting intestinal motility.
First-line approaches and their limitations
Initial treatment for most constipation includes dietary fiber, hydration, and exercise. Over-the-counter laxatives are used when lifestyle changes are insufficient. Osmotic laxatives like polyethylene glycol (PEG) draw water into the colon to soften stool, often used first for chronic constipation. Stimulant laxatives, such as senna and bisacodyl, stimulate intestinal contractions. However, these are often less effective in STC patients who have reduced colonic motor response. Prescription medications are needed to address the specific motility problems.
Prescription medications for slow transit constipation
Prucalopride (Motegrity)
Prucalopride is a prokinetic, a selective serotonin (5-HT4) receptor agonist that stimulates 5-HT4 receptors in the gut to enhance peristalsis and increase bowel movement frequency. It is effective for STC by promoting coordinated colonic movements. Common side effects include headache, nausea, abdominal pain, and diarrhea. Rare side effects include mood changes or suicidal thoughts, requiring monitoring.
Lubiprostone (Amitiza)
Lubiprostone is a chloride channel activator approved for chronic idiopathic constipation. It increases fluid secretion in the small intestine, softening stool and increasing transit time. It activates ClC-2 chloride channels, increasing water and chloride influx into the intestine to facilitate stool passage. Nausea and diarrhea are common side effects, which may be reduced by taking the medication with food and water. Other reported side effects include dizziness and chest discomfort.
Linaclotide (Linzess)
Linaclotide is a guanylate cyclase-C (GC-C) agonist for chronic idiopathic constipation. It increases intestinal fluid secretion and accelerates gastrointestinal transit. It increases cGMP levels by acting on GC-C receptors, leading to increased fluid secretion and faster waste movement. It also helps reduce abdominal pain. Diarrhea is the most frequent and potentially severe side effect. Abdominal pain, bloating, and gas are also common. Linaclotide has a boxed warning for serious dehydration risk in pediatric patients under 2 years old.
Plecanatide (Trulance)
Plecanatide is another GC-C agonist for chronic idiopathic constipation. Similar to linaclotide, it increases intestinal fluid and promotes regular bowel movements. It increases cGMP and fluid secretion into the intestines to aid stool passage. Diarrhea is the most common side effect. Abdominal bloating and gas can also occur. Plecanatide also has a boxed warning for severe dehydration risk in children under 6 years old.
Comparison of Prescription Medications
| Feature | Prucalopride (Motegrity) | Lubiprostone (Amitiza) | Linaclotide (Linzess) | Plecanatide (Trulance) |
|---|---|---|---|---|
| Drug Class | Prokinetic (5-HT4 agonist) | Chloride Channel Activator (Prostone) | GC-C Agonist | GC-C Agonist |
| Mechanism | Stimulates colonic muscle contractions for movement | Increases intestinal fluid secretion | Increases intestinal fluid secretion and transit time | Increases intestinal fluid secretion and transit time |
| Evidence in STC | Strong evidence; specifically targets motility | Limited direct studies, but effective for severe CIC | Limited direct studies, but effective for severe CIC | Limited direct studies, but effective for severe CIC |
| Primary Use | Chronic Idiopathic Constipation (CIC) | CIC, IBS-C, Opioid-induced constipation | CIC, IBS-C | CIC, IBS-C |
| Administration | Oral tablet, once daily | Oral capsule, twice daily | Oral capsule, once daily | Oral tablet, once daily |
| Common Side Effects | Headache, nausea, diarrhea, stomach pain | Nausea, diarrhea, headache | Diarrhea, abdominal pain, bloating, gas | Diarrhea, bloating, gas |
| Pediatric Warning | Yes, monitor for mood/behavior changes | Not for use if pregnant/breastfeeding (Category C) | Yes, not for under 2 years | Yes, not for under 6 years |
Combining treatments
For refractory STC, combining pharmacological and non-pharmacological therapies may be necessary, such as a prokinetic with a fiber supplement or osmotic laxative under medical supervision. Biofeedback therapy for co-occurring pelvic floor dysfunction has also shown potential for improving symptoms and reducing laxative dependence.
The role of surgery
Surgery may be considered a last resort for severe STC unresponsive to all medical treatments. Procedures like colectomy with ileorectal anastomosis are typically only performed after a comprehensive evaluation confirms STC and rules out other causes, and all other treatment options are exhausted.
Conclusion
For those asking what medication is used for slow transit constipation, the choice depends on severity and the specific physiological issue. While initial treatment may involve osmotic or stimulant laxatives, dedicated prescription therapies are available for more severe, transit-related problems. Prucalopride, a prokinetic, is a preferred option for true STC due to its ability to enhance colonic motility. Secretagogues like lubiprostone, linaclotide, and plecanatide increase intestinal fluid to soften stool and speed transit. A healthcare provider will determine the most suitable medication based on individual needs and potential side effects. Other therapies, including surgery, are options for those who do not respond to medication.
How to get started
If you suspect you have STC, consult a gastroenterologist. They can provide a thorough evaluation and guide you through treatment options. Reliable information on digestive health is available from sources like the National Institute of Diabetes and Digestive and Kidney Diseases: [https://www.niddk.nih.gov/health-information/digestive-diseases/constipation].
References
- American Academy of Family Physicians (AAFP). (2006). Lubiprostone (Amitiza) for Chronic Idiopathic Constipation. American Family Physician, 74(8), 1380-1382.
- Cleveland Clinic. (2025). Constipation: Symptoms & Causes.
- Columbia Doctors. (2025). Prucalopride.
- Drugs.com. (2025). Linaclotide Side Effects.
- GoodRx. (2025). Motegrity (prucalopride): Side Effects, Uses, Dosage & More.
- Mayo Clinic. (2025). Constipation - Diagnosis and treatment.
- Mayo Clinic. (2025). Prucalopride (oral route).
- Mayo Clinic. (2025). Lubiprostone (oral route).
- Mayo Clinic. (2025). Linaclotide (oral route).
- Mayo Clinic. (2025). Plecanatide (oral route).
- Medical News Today. (2022). Best medications for constipation.
- MedlinePlus. (2023). Linaclotide: MedlinePlus Drug Information.
- MDPI. (2024). Idiopathic Slow Transit Constipation: Pathophysiology and Advanced Pharmacologic Therapies.
- National Institutes of Health (NIH) | PMC. (2008). Update on constipation: One treatment does not fit all.
- National Institutes of Health (NIH) | PMC. (2017). Functional Disorders: Slow-Transit Constipation.
- National Institutes of Health (NIH) | PMC. (2020). Treatment of slow transit constipation-induced ileus during pregnancy.
- Physiopedia. (2025). Slow Transit Constipation.
- WebMD. (2024). Trulance (plecanatide) - Uses, Side Effects, and More.
What medication is used for slow transit constipation? FAQs
Q: Is Miralax or other over-the-counter laxatives effective for slow transit constipation? A: While osmotic laxatives like Miralax (polyethylene glycol) may provide some benefit, they often fail in cases of true slow transit constipation (STC). They are usually tried first, but if unsuccessful, prescription medication is often needed.
Q: How do prescription medications differ from over-the-counter options for STC? A: Prescription medications, such as prokinetics (prucalopride) and secretagogues (lubiprostone, linaclotide, plecanatide), are specifically designed to address the underlying nerve and muscle issues causing slow colonic movement, rather than just softening stool or stimulating a general bowel movement.
Q: What is the main difference between prucalopride and the other prescription options like linaclotide? A: Prucalopride is a prokinetic that directly stimulates colon muscle contractions to improve motility, making it a powerful tool for confirmed STC. Linaclotide and similar drugs are secretagogues that increase intestinal fluid to help move waste along.
Q: What are the common side effects of prescription STC medications? A: Common side effects vary by medication but frequently include diarrhea, abdominal pain, nausea, and headache. A doctor can help manage these and may adjust the dosage or recommend taking the medication with food.
Q: Can I take these medications long-term? A: These medications are intended for long-term use in chronic conditions, but long-term safety and efficacy are monitored in clinical trials. Your healthcare provider will regularly assess your progress to ensure continued safety and effectiveness.
Q: Are there any warnings for specific patients? A: Yes. Linaclotide and plecanatide carry warnings for children, and prucalopride has warnings related to mood and behavior changes. Patients with certain conditions, like intestinal blockages, should not take these medications.
Q: Is surgery an option for slow transit constipation? A: Surgery, such as a colectomy, is a last-resort option reserved for severe cases of STC that do not respond to all other medical and lifestyle treatments. It is not a common treatment and is only pursued after a comprehensive evaluation.
Q: How can diet and lifestyle changes help manage slow transit constipation? A: Dietary changes, such as increasing fiber and water intake, and lifestyle modifications like regular exercise can help improve stool consistency and encourage bowel movements. However, these are often insufficient alone for individuals with confirmed STC.
