DOSAGE AND ADMINISTRATION
For safety reasons, only physicians who enroll in the Prometheus Prescribing Program for LOTRONEX should prescribe LOTRONEX (see PRECAUTIONS: Prescribing Program for LOTRONEX).
Usual Dosage in Adults
To lower the risk of constipation, LOTRONEX should be started at a dosage of 0.5 mg twice a day. Patients well controlled on 0.5 mg twice a day may be maintained on this regimen. If, after 4 weeks, the 0.5-mg twice-daily dosage is well tolerated but does not adequately control IBS symptoms, then the dosage can be increased to up to 1 mg twice a day, the dose used in controlled clinical trials (see CLINICAL TRIALS). LOTRONEX should be discontinued in patients who have not had adequate control of IBS symptoms after 4 weeks of treatment with 1 mg twice a day.
LOTRONEX can be taken with or without food (see CLINICAL PHARMACOLOGY: Pharmacokinetics: Food Effects).
LOTRONEX should be discontinued immediately in patients who develop constipation or signs of ischemic colitis. LOTRONEX should not be restarted in patients who develop ischemic colitis.
Clinical trial and postmarketing experience suggest that debilitated patients or patients taking additional medications that decrease gastrointestinal motility may be at greater risk of serious complications of constipation. Therefore, appropriate caution and follow-up should be exercised if LOTRONEX is prescribed for these patients (see also Geriatric Patients).
Safety and effectiveness have not been established in pediatric patients.
Postmarketing experience suggests that elderly patients may be at greater risk for complications of constipation; therefore, appropriate caution and follow-up should be exercised if LOTRONEX is prescribed for these patients (see WARNINGS).
Patients With Renal Impairment
There is insufficient data available on the biological activity of the metabolites of LOTRONEX. It is unknown if dosage adjustment is needed in patients with renal impairment (see CLINICAL PHARMACOLOGY: Population Subgroups: Reduced Renal Function).
Patients With Hepatic Impairment
LOTRONEX is extensively metabolized by the liver and increased exposure to LOTRONEX is likely to occur in patients with hepatic impairment. Increased drug exposure may increase the risk of serious adverse events. LOTRONEX should be used with caution in patients with mild or moderate hepatic impairment and is contraindicated in patients with severe hepatic impairment (see CLINICAL PHARMACOLOGY: Population Subgroups: Reduced Hepatic Function, CONTRAINDICATIONS, and PRECAUTIONS: Hepatic Insufficiency).
Information for Pharmacists
LOTRONEX may be dispensed only on presentation of a prescription for LOTRONEX with a sticker for the Prescribing Program for LOTRONEX attached. A Medication Guide for LOTRONEX must be given to the patient each time LOTRONEX is dispensed as required by law. No telephone, facsimile, or computerized prescriptions are permitted with this program. Refills are permitted to be written on prescriptions .