Lubiprostone (Amitiza)

What is Lubiprostone?

Lubiprostone, marketed under the brand name Amitiza in some markets, is a bicyclic fatty acid derived from prostaglandin E1. It is classified as a selective chloride channel activator and is used in the management of constipation-predominant gastrointestinal disorders, including:

• Chronic Idiopathic Constipation (CIC): Constipation without a known underlying cause, occurring in both men and women
• Irritable Bowel Syndrome with Constipation (IBS-C): IBS characterised predominantly by constipation, bloating, and abdominal discomfort
• Opioid-Induced Constipation (OIC): Constipation as a side effect of opioid pain medicines in adults with chronic non-cancer pain

Lubiprostone is a targeted pharmacological approach to constipation, working at the cellular level in the intestinal lining rather than stimulating gut contractions or acting via an osmotic mechanism.

How does Lubiprostone work?

Lubiprostone selectively activates type-2 chloride channels (ClC-2 channels) located in the apical membrane of intestinal epithelial cells — the cells lining the inner surface of the intestine. When these channels are activated:

1. Chloride secretion: Chloride ions flow from the epithelial cells into the intestinal lumen (the interior space of the gut).
2. Fluid follows: Sodium ions and water follow the chloride gradient via paracellular pathways, increasing intestinal fluid secretion.
3. Stool softening: The increased luminal fluid softens stool consistency.
4. Peristalsis facilitated: Softer, more fluid stool moves more easily through the colon, facilitating natural bowel movements.

Because Lubiprostone acts specifically on ClC-2 channels rather than on prostaglandin receptors systemically, its effects are largely localised to the intestinal lining. It is minimally absorbed into the systemic circulation, which limits systemic side effects.

For IBS-C, Lubiprostone also appears to reduce intestinal permeability and may have modest anti-inflammatory effects on the intestinal mucosa, which may contribute to its benefit beyond simple stool softening.

Who is Lubiprostone for?

Lubiprostone is indicated for adults who:

• Have chronic constipation that has not responded adequately to dietary fibre, hydration optimisation, and conventional over-the-counter laxatives
• Have a diagnosis of IBS-C and require pharmacological management beyond antispasmodics and dietary measures
• Are experiencing constipation as a side effect of prescribed opioid pain medicines

Lubiprostone is not suitable for:

• Patients with known or suspected mechanical gastrointestinal obstruction (e.g., from adhesions, tumour, or stricture)
• Patients with severe diarrhoea
• Pregnant women (potential for fetal harm — Category C designation in clinical guidance)
• Patients with known hypersensitivity to Lubiprostone

Lubiprostone requires assessment by a qualified doctor before initiation, as symptoms of constipation and IBS-C can overlap with conditions requiring different management.

Dosage

For adults, dosing guidance based on published clinical information is:

Indication	Dose	Frequency
Chronic Idiopathic Constipation	24 mcg	Twice daily with food
IBS-C (women 18+)	8 mcg	Twice daily with food
Opioid-Induced Constipation	24 mcg	Twice daily with food

Lubiprostone capsules should always be taken with food and water to reduce nausea, the most common side effect. An independent doctor will prescribe the appropriate dose for your specific diagnosis and circumstances.

Side effects

Common side effects

• Nausea: The most frequently reported side effect, reported in up to 29% of patients in clinical trials. Taking Lubiprostone with food significantly reduces this.
• Diarrhoea: May occur, particularly with the 24 mcg dose.
• Abdominal pain or discomfort
• Headache
• Abdominal distension (bloating)

Less common side effects

• Flatulence (gas)
• Vomiting
• Fatigue
• Dizziness
• Oedema (fluid retention)

Serious but rare side effects

• Dyspnoea (shortness of breath): Some patients (approximately 3% in clinical trials) have reported breathlessness, typically within 1 hour of the first dose. This resolves spontaneously but should be reported to a doctor.
• Severe diarrhoea or electrolyte disturbance: With prolonged use at higher doses

Lubiprostone vs alternatives for chronic constipation and IBS-C

Medicine	Class	Mechanism	Best for
Lubiprostone	ClC-2 activator	Increases intestinal fluid secretion	CIC, IBS-C, OIC
Linaclotide	GC-C agonist	Increases fluid + reduces visceral pain	IBS-C, CIC
Prucalopride	5-HT4 agonist	Increases gut motility	CIC resistant to standard laxatives
Macrogol (PEG)	Osmotic laxative	Draws water into colon	Acute and chronic constipation
Bisacodyl	Stimulant laxative	Stimulates colonic contractions	Short-term acute constipation

For IBS-C specifically, Lubiprostone is one of the few prescription agents with clinical trial data supporting both improvement in constipation and reduction in associated abdominal pain and bloating.

How to get Lubiprostone online in Europe

Lubiprostone is a prescription-only medicine. Prescrivia operates as a technology intermediary — we do not prescribe medicines, employ doctors, or sell medicines. Our platform connects patients with independent EU-registered doctors who can conduct online digestive health assessments.

The process:

1. Complete a digestive health assessment: Describe your symptoms, frequency, severity, previous treatments tried, and relevant medical history.
2. Doctor review: An independent EU-registered doctor reviews your assessment and determines whether Lubiprostone or an alternative management approach is appropriate.
3. Prescription and fulfilment: If a prescription is issued, it is forwarded to a licensed EU pharmacy partner for dispensing and delivery.

Important: Prescrivia does not guarantee that a prescription will be issued. All prescribing decisions are made independently by qualified medical professionals.

Important safety information

Do not take Lubiprostone if you:

• Have known or suspected mechanical gastrointestinal obstruction
• Are pregnant (or planning to become pregnant — contraception required during treatment)
• Have severe diarrhoea
• Are hypersensitive to Lubiprostone or any excipient

Tell your doctor if you:

• Have liver disease (dose reduction may be needed for IBS-C in patients with moderate-to-severe hepatic impairment)
• Experience new shortness of breath within an hour of your first dose
• Have severe diarrhoea at any point during treatment (reduce dose or stop and contact your doctor)

Seek urgent medical advice if you develop:

• New, severe, or sudden abdominal pain
• Blood in stools or black/tarry stools
• Unexplained weight loss

These may indicate conditions requiring urgent evaluation beyond the scope of constipation management.

Sources

Medical information on this page is based on the following sources:

• Johanson JF, Ueno R. Lubiprostone, a locally acting chloride channel activator, in adult patients with chronic constipation: a double-blind, placebo-controlled, dose-ranging study to evaluate efficacy and safety. Aliment Pharmacol Ther. 2007.
• Drossman DA, et al. Clinical trial: Lubiprostone in patients with constipation-associated irritable bowel syndrome — results of two randomized, placebo-controlled studies. Aliment Pharmacol Ther. 2009.
• European Medicines Agency (EMA). Relevant product information and assessment reports. ema.europa.eu
• World Health Organization (WHO). Diarrhoeal disease and gastrointestinal health. who.int

This content is provided for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional for advice relevant to your individual health circumstances.