Lubiprostone is a locally-acting chloride-channel activator that increases intestinal secretion. In doing so, it increases intestinal motility, thus aiding the passage of stool and relieve the symptoms associated with chronic idiopathic constipation.

Lubiprostone acts by specifically activating ClC-2 chloride channels, which is a normal constituent of the apical membrane of the human intestine, in a protein kinase A action independent fashion. Activation of ClC-2 chloride channels causes an efflux of chloride ions into the lumen, which in turn leads to an efflux of sodium ions through a paracellular pathway to maintain isoelectric neutrality. As a result, water follows sodium into the lumen in order to maintain isotonic equilibrium, thereby increasing intestinal fluid secretion. By increasing intestinal fluid secretion, lubiprostone increases motility in the intestine, thereby increasing the passage of stool and alleviating symptoms associated with chronic idiopathic constipation. Activation of ClC-2 chloride channels may also stimulate the recovery of muscosal barrier function by restoring tight junction protein complexes in the intestine. Patch clamp cell studies in human cell lines have indicated that the majority of the beneficial biological activity of lubiprostone and its metabolites is observed only on the apical (luminal) portion of the gastrointestinal epithelium.

Lubiprostone is indicated in:

• Irritable Bowel Syndrome with Constipation (IBS-C).
• Chronic Idiopathic Constipation (CIC) in adults.
• Opioid-Induced Constipation (OIC) in adult patients with chronic, non-cancer pain.

Irritable Bowel Syndrome with Constipation: The recommended dose is 8 mcg twice daily orally with food and water.

Dosage in patients with hepatic impairment: Dosage adjustment is not required for patients with moderately impaired hepatic function. For patients with severely impaired hepatic function, the recommended starting dose is 8 mcg once daily. If tolerated then dose can be increased to 8 mcg twice 

Chronic Idiopathic Constipation and Opioid-induced Constipation: The recommended dose is 24 mcg twice daily orally with food and water. 

Dosage in patients with hepatic impairment: For patients with moderately impaired hepatic function, the recommended starting dose is 16 mcg twice daily. For patients with severely impaired hepatic function, the recommended starting dose is 8 mcg twice daily.

Lubiprostone is contraindicated in patients with known or suspected mechanical gastrointestinal obstruction.

Diarrhea, full or bloated feeling or pressure in the stomach, nausea, stomach pain, swelling of abdominal or stomach area, Dyspnea

Overdose Effects

Adverse reactions due to overdose may include: nausea, diarrhea, vomiting, dizziness, headache, abdominal pain, flushing/hot flash, retching, dyspnea, pallor, stomach discomfort, anorexia, asthenia , chest discomfort, dry mouth, hyperhidrosis , and syncope.

Nausea: Patients taking Lubiprostone may experience nausea. Concomitant administration of food with Lubiprostone may reduce symptoms of nausea.

Diarrhea: Lubistone should not be prescribed to patients that have severe diarrhea.

Bowel Obstruction: In patients with symptoms suggestive of mechanical gastrointestinal obstruction, perform a thorough evaluation to confirm the absence of an obstruction prior to initiating therapy with Lubiprostone.

Pregnancy & Lactation

Pregnancy category C. It is not known whether lubiprostone is excreted in human milk. Because lubiprostone increases fluid secretion in the intestine and intestinal motility, human milk-fed infants should be monitored for diarrhea. Caution should be exercised when Lubiprostone is administered to a nursing woman.