Lubiprostone (Amitiza) acts in the gastrointestinal lumen and increase the GI transit and intestinal fluid secretion.

Lubiprostone (Amitiza) Indications:

• It is indicated in the treatment of the following conditions:

  • Chronic idiopathic constipation (CIC) in adults
  • Irritable bowel syndrome (IBS) with constipation
  • Opioid-induced constipation (OIC) in adult patients with chronic pain related to prior cancer or its treatment who do not require frequent opioid dose escalation.

Lubiprostone (Amitiza) Dose in Adults:

Lubiprostone (Amitiza) Dose in the treatment of chronic idiopathic constipation:

• 24 mcg orally two times a day.

Dose in the treatment of Irritable bowel syndrome with constipation in females 18 years of age or more:

• 8 mcg orally two times a day

Lubiprostone (Amitiza) Dose in the treatment of opioid-induced constipation:

• 24 mcg orally two times a day.

Lubiprostone (Amitiza) dose in children:

The safety and efficacy of the drug in children have not been established.

Pregnancy Risk Category: C

• Negative fetal outcomes have been documented in animal reproduction studies.

Use of lubiprostone while breastfeeding

• It is unknown whether the active metabolite or drug are excreted into breastmilk.
• Manufacturer recommends that you monitor your infant for signs of diarrhea.
• Manufacturers recommend weighing the risks to the infant from drug exposure and the benefits for the mother.

Dose in Kidney disease:

Adjustment in the dose is not necessary.

Lubiprostone (Amitiza) Dose in Liver disease:

• Mild hepatic impairment (Child-Pugh class A):

  • No dosage adjustment is necessary.

• Moderate hepatic impairment (Child-Pugh class B):

  • Chronic idiopathic constipation or opioid-induced constipation:

    • 16 mcg two times a day initially.
    • The dose may be increased to 24 mcg two times a day if an adequate response has not been obtained and the drug is tolerated.

  • Irritable bowel syndrome with constipation:

    • Adjustment in the dose is not necessary.

• Severe hepatic impairment (Child-Pugh class C):

  • Chronic idiopathic constipation or opioid-induced constipation:

    • 8 mcg two times a day initially.
    • The dose may be increased to 16 to 24 mcg two times a day if an adequate response has not been obtained and the drug is tolerated.

  • Irritable bowel syndrome with constipation:

    • 8 mcg once a day initially.
    • The dose may be increased to 8 mcg two times a day if an adequate response has not been obtaine and the drug is well tolerated.

Common Side Effects of Lubiprostone (Amitiza):

• Central nervous system:

  • Headache

• Gastrointestinal:

  • Nausea
  • Diarrhea

Less Common Side Effects of Lubiprostone (Amitiza):

• Cardiovascular:

  • Edema
  • Chest discomfort
  • Chest pain
  • Peripheral edema

• Central nervous system:

  • Dizziness
  • Fatigue

• Gastrointestinal:

  • Abdominal pain
  • Flatulence
  • Abdominal distention
  • Abdominal distress
  • Loose stools
  • Vomiting
  • Dyspepsia
  • Xerostomia

• Respiratory:

  • Dyspnea

Contraindications to Lubiprostone (Amitiza):

Patients with a suspected or known mechanical GI (gastrointestinal obstruction) are not advised to use it.

Warnings and precautions

• Dyspnea
  • Dyspnea can occur after the first dose. It may manifest as tightness in the chest and difficulty taking deep breaths.
  • Dyspnea can occur immediately (within 30-60 minutes) following the first dose. However, it has been reported to also occur with subsequent dosing.
• Nausea:
  • To reduce nausea and improve GI tolerability, the drug should be taken with food
• Hypotension and syncope:
  • Syncope and hypotension may occur when the drug is combined with antihypertensive medications or higher doses.
  • Hypotension can occur after the first dose. It will usually resolve before the next scheduled dose or after discontinuation.
  • Patients may require hospitalization in severe cases.
• Diarrhea:
  • Patients with severe diarrhea should avoid it.
• Gastrointestinal obstruction:
  • Patients with mechanical gastrointestinal obstruction should avoid it.
  • Before prescribing any drug, all patients must be examined for mechanical GI obstruction.
• Hepatic impairment
  • Patients with severe or moderate hepatic impairment may be at greater risk of drug exposure. Adjustments in doses may be necessary.

Lubiprostone: Drug Interaction

Monitor:

• Bowel frequency and consistency
• Liver function tests at baseline and periodically as indicated.

How to administer Lubiprostone (Amitiza)?

Oral: Administer with food and water. Swallow whole; do not break or chew.

Mechanism of action of Lubiprostone (Amitiza):

• It acts locally on the apical membrane in the gastrointestinal tract and is a chloride channel activater.
• This bypasses the antisecretory effects opiates have on secretomotor neuron excitability.

Absorption:

• The systemic absorption of the parent drug is poor while that of the active metabolite is low.

Distribution

• beyond the gastrointestinal tract is minimal.

Plasma proteins binding:

• 94%

Metabolism:

• Extensively within the stomach and jejunum by carbonyl reductase to active (M3) and inactive metabolites rapidly.

Bioavailability:

• The bioavailability of the drug is minimal

Half-life elimination

• The half-life elimination of the active metabolite (M3) is 0.9 to 1.4 hours

The time to reach peak plasma concentration:

• about 1.1 hours for the active metabolite (M3).

Excretion:

• Parent drug and M3: Feces (trace amounts)

International Brands of Lubiprostone:

• Amitiza
• Amiprostone
• Lubilax
• Lubistone
• Lubowel
• Lupicont
• Luprostam
• Modulex

Lubiprostone Brand Names in Pakistan:

No Brands Available in Pakistan.