AMITIZA

Following oral administration, concentrations of lubiprostone in plasma are below the level of quantitation (10 pg/mL). Therefore, standard pharmacokinetic parameters such as area under the curve (AUC), maximum concentration (C max ), and half-life (t ½ ) cannot be reliably calculated. However, the pharmacokinetic parameters of M3 (only measurable active metabolite of lubiprostone) have been characterized.

AbsorptionPeak plasma concentrations of M3, after a single oral dose of 24 mcg of lubipro...

14.1 Chronic Idiopathic Constipation in Adults Two double-blinded, placebo-controlled studies of identical design were conducted in patients with CIC. CIC was defined as, on average, less than 3 SBMs per week (a SBM is a bowel movement occurring in the absence of laxative use) along with one or more of the following symptoms of constipation for at least 6 months prior to randomization: 1) very hard stools for at least a quarter of all bowel movements; 2) sensation of incomplete evacuation following at least a quarter of all bowel movements; and 3) straining with defecation at least a quarter o...

The following adverse reactions are described below and elsewhere in labeling: Nausea [see Warnings and Precautions (5.1) ] Diarrhea [see Warnings and Precautions (5.2) ] Syncope and Hypotension [see Warnings and Precautions (5.3) ] Dyspnea [see Warnings and Precautions (5.4) ] Most common adverse reactions (> 4%) are: CIC: nausea, diarrhea, headache, abdominal pain, abdominal distension, and flatulence. ( 6.1 ) OIC: nausea and diarrhea. ( 6.1 ) IBS-C: nausea, diarrhea, and abdominal pain. ( 6.1...

Amitiza is contraindicated in patients with known or suspected mechanical gastrointestinal obstruction [see Warnings and Precautions (5.5) ] . Patients with known or suspected mechanical gastrointestinal obstruction. ( 4 , 5.5 )

Nausea : Patients may experience nausea; concomitant administration of food may reduce this symptom. ( 2.2 , 5.1 ) Diarrhea : Avoid use in patients with severe diarrhea. Instruct patients to discontinue Amitiza and contact their healthcare provider if severe diarrhea occurs during treatment. ( 5.2 ) Syncope and Hypotension : May occur after taking the first dose or with subsequent doses. Generally resolves prior to the next dose, but may recur with repeat dosing. Instruct patients to discontinue...

7 DRUG INTERACTIONS 7.1 Methadone Diphenylheptane opioids (e.g., methadone) have been shown in nonclinical studies to dose-dependently reduce the activation of ClC-2 by lubiprostone in the gastrointestinal tract. There is a possibility of a dose-dependent decrease in the efficacy of Amitiza in patients using diphenylheptane opioids. No in vivo interaction studies have been conducted. The effective...